for Irish Traditional Musicians

updated: 5/10/18

The purpose of the following discussion is to help you, as a backup player or composer, find appropriate chords for accompanying Irish tunes or songs. The determination of what constitutes an appropriate chord is based on the most likely harmonizations of the accented melody note in the particular key.

"Harmonization" is a five-syllable word meaning "putting a chord to a note"

I've tried to make it as un-technical as possible, but the fullest understanding of what's going on requires a certain familiarity on your part with terms like "relative minors" and "scales" (being familiar with Roman numerals helps too!) If you're not comfortable in this area, you can skip right to the chord tables.

What follows should not be viewed as a rigid set of rules, but rather as a guide to what will usually sound best. I have tried to list the chords by degree of suitability, i.e. the first one listed is the most likely one to produce the harmonization suitable to the tune or song. This cannot however be anything more than a suggestion; your own musical ear (and those of the musicians around you, as you'll soon find out!) will make the ultimate decision.




Pitch / note / tone
The name for a distinct musical sound of a given vibration. Popularly used interchangeably with "note" although technically they are not the same. The term "tone" is used for the same purpose and will be the one I use in this document.

Step or interval
The distance between two adjoining tones; based on acoustic concepts too technical to deal with here. The important thing to know is that our branch of so-called Western music deals in "whole steps" and "half steps".  (I should note here that for equally technical reasons, the interval from B to C and from E to F is always a half-step, regardless of what the alphabet is telling you!)

The tones starting from the "tonic" and working up to the "octave".  There are two kinds of scale (bear with me here): the diatonic scale (= the "do, re, mi" we all know and love). Contains eight notes. Example: C, D, E, F, G, A, B, C'. the chromatic scale, which contains twelve notes. Example: C, C#, D, D#, E, F, G, G#, A, A#, B, C'.

(The purpose of "accidentals" [sharps and flats] is to indicate half-step alterations in tones - a sharp moves a tone upwards a half-step, while a flat lowers it.)

Think of it this way:

If you play a fiddle, two- or three-row accordion, concertina, keyed flute, or fretted instrument, you're playing a chromatic instrument because you can play all the notes of the chromatic scale (corresponding to the white + black keys on the piano).

However, if you play the wooden flute, whistle or harmonica, you're playing a diatonic instrument, since most of the "half-steps" necessary for the chromatic scale are not readily available to you. (When we talk about "D whistles" we mean whistles designed to play the D scale. We don't talk about "G fiddles" because fiddles, as chromatic instruments, can play any scale.)

Since the idea of the seven-note-plus-octave diatonic scale is more useful to this discussion, any reference to "scale" henceforth will automatically refer to a "diatonic" scale.

It's important to note that each member of a scale has a corresponding number called a "scale degree".  This enables us to discuss musical relationships without worrying about the pitches involved. Scale degrees are usually indicated by Roman numerals, which also serve as shorthand for the chords built on those pitches (but we're getting a little ahead of ourselves here).

Major, minor
Scales can be "major" or "minor" depending on the arrangement of the whole steps and half steps between their pitches. This is pretty important, so a full explanation will follow later.

Note in the meantime that every major scale has a corresponding ("relative") minor scale that starts on the sixth scale degree (thus A in the key of C). Not surprisingly, every minor scale has a "relative major" that starts on the third scale degree (thus C in the key of A minor). They are called "relative" because each pair has the same key signature

This is an important relationship in Irish music and helps to make tunes like "Sailor's Bonnet" (first part in D major, second part in its "relative" B minor), "Curragh Races" (A minor - C major), or "Leitrim Fancy" (E minor - G major) sound the way they do.

The best way to describe a "mode" is to think of it as a slightly altered scale, i.e. one in which the pitches are related in ways that make the scale not quite major or not quite minor.

This of course is "Music Theory for Dummies" material, but the truth is that the subject of modes is a complicated one and best left to the editors of the Harvard Dictionary of Music to explain. For the purposes of Irish traditional music, however, the situation is made bearable by the fact that there are really only two modes to worry about (and easy enough to understand once you get past the names): the "mixolydian" mode (a major scale where the 7th scale degree is alwaysflatted, ex. G-A-B-C-D-E-F natural-G') and the "aeolian" mode (a minor scale where the 6th scale degree is always
sharped, ex. A - B - C - D - E - F# - G - A).

When Irish musicians talk about "modal" tunes (if they ever do), they are referring to the mixolydian tunes like "Rakish Paddy", "Cook in the Kitchen", "Fairhaired Boy", and the like, where most if not all of the accented 7th degree pitches (C in "Paddy", F in "Cook", G in "Boy") are played a half-step lower than the key signature would indicate. The sound of a modal tune is quite distinctive, as the examples I cited will make clear.

The Aeolian mode is almost the default for Irish traditional tunes. I can't think offhand of any minor-key tunes that consistently use the "plain" sixth, i.e. C instead of C# in the key of E minor, F natural instead of F# in A minor, etc. I'm sure there are some but they are a distinct minority of the repertoire.

Not a Chinese gang but a three-note chord built on the notes of the scale. Every note has its corresponding triad. Very important, so more on this later.

Another way of saying what scale we'll be using in a particular tune. If you know that a tune is in the key of D, for example, you can expect all the C's and F's to be sharp (if you're reading the music, the tune's key signature will remind you). "Tonality" is a fancy way of saying "key".

For a backup player, once you know the key, you know what chords you can expect to play.

To expedite the learning process, I present here the important keys in traditional music along with their corresponding key signatures (= the sharps and flats right after clef at the beginning of the tune) and relative minors:

C major
no sharps or flats
A minor
G major
one sharp
E minor
D major
two sharps
B minor
A major
three sharps
F# minor
F major
one flat
D minor
Bb major
two flats
G minor

Scale degrees
Disclaimer: I said at the beginning that I would try to make this discussion as un-technical as possible, but unhappily the concepts, though important and ultimately helpful, are a little complex. If you start the following but find yourself getting glazed eyes, skip it and go on to the next section!

s mentioned earlier, musical convention requires the use of Roman numerals to describe the relationship between notes (and the triads built on them) in any scale. Not surprisingly, the "tonic" (= first note of the scale) is always I.

Example: the classic rock-and-roll chord progression is I - VI - IV - V, which means in musical shorthand that the chords are built on the first ("tonic") scale degree, on the sixth, on the fourth, and on the fifth. In the key of D, these chords would be D, B(minor), G, and A (why the VI chord is minor will be discussed in the section on Triads).

The handy aspect of the Roman numeral convention is the fact that the chord relationships (a/k/a "progressions") remain the same regardless of key. The R & R I - VI - IV - V progression will produce the same sound regardless of what the I chord is. Remember: the Roman numerals are giving you information about the chord relationships, not the actual chords themselves.

Another example: if you tell somebody that the basic harmony for an Irish traditional tune in a minor key consists of a I - VII relationship, that's shorthand for saying "for a tune in E minor, your secondary chord is D; for a tune in B minor, you'll be hearing a lot of A; for a tune in Dm, look for C", etc. etc.

Sounds handy, right? In fact it is, and even better it's very simple to learn how to match notes and numbers to start the whole procedure going.

There are names that go along with the Roman numerals. I list these names here just in case you come across them somewhere:
scale degree I...................... tonic or root
scale degree IV................... subdominant (ex. D E F# G A B C# D')
scale degree V.................... dominant (ex. D E F# G A B C# D')
scale degree VII.................. leading tone (ex. D  E  F# G  A  B  C#  D')

The scale starting on degree VI of a major scale is the "relative minor" of that scale. (Ex. D E F# G A B C# D')
The scale starting on degree III of a minor scale is the "relative major" of that scale. (Ex. A B C D E F G A')

"Relative" major/minor scales share the same key signature (per the table a few paragraphs above).

It happens occasionally that a musician has to change the key of a piece (to enable easier playing on a particular instrument, for example). This process is referred to as transposing.

Based on the theory (that will be elaborated below) that the pitches in all major scales bear the same distance relationship to one another,  transposing from one key to another is actually very simple.

Here's the way I do it: I write the numbers 1 to 7 in a column down the page, put the notes of the original key in the second column, then put the notes of the new key in the third column. (Remember to make sure that you insert all the flats or sharps that the keys require, or else you'll wind up with a really weird sound!)

You don't really need the first column - as long as you remember to match the tonic notes of the old and new keys, the rest of the notes will more or less take care of themselves.

In the following examples, we'll suppose that we have
[1] a piece in the key of D major that we want to transpose into the key of F major
[2] a piece in the key of E minor that we want to transpose into the key of A minor

                                                                                Example 1:
scale degree
key of D
key of F

                                                                                                               Example 2:

scale degree
key of Em
key of Am

This system will work for chords too: in example 1, an F# minor chord in D will transpose to an A minor chord in F; in example 2, a B minor chord in E minor will transpose to an E minor chord in A minor. (It's a lot simpler than it sounds!)

Always remember: when transposing chords, majors transpose to majors and minors transpose to minors.


This is the time to talk more about "triads", which are the building blocks of chords in Western music for reasons that go back thousands of years to the ancient Greeks (who came up with a lot of concepts still valid today).

A "triad" is a collection of notes that consists of a root, a third, and a fifth. In Roman numerals, a triad = I - III - V.
Ex. 1:   D major triad = I - III - V = D   E   F#   G   A   B   C#   D'
Ex. 2:   G major triad = I - III - V = G   A   B   C   D   E   F#   G'

Since the relationship between the I and the III can change, depending on whether the scale involved is major or minor,
we can have minor triads too:
Ex. 3:   D minor triad = I - III - V = D   E   F   G   A   Bb   C   D'
Ex. 4:   G minor triad = I - III - V = G   A   Bb   C   D   Eb   F   G'

(Note that you can add the octave pitch to any chord without affecting it - for chord purposes, it's still considered a "I" even though it's an octave higher.)

[b] Chords where the third or fifth scale degrees are in the lowest position (e.g. F# - D - A or A - D - F#) are said to be "inverted". If III is the lowest tone, the chord is in "first inversion"; if V is the lowest, it's in "second inversion". But either way it's still called by its root name (in this case, a D chord).

1. There are chords called "seventh" chords (abbreviated V7 or Vb7) that have four scale members instead of three: the root, third, fifth, and the seventh. (Don't confuse a "seventh" chord - which means a V chord with an added seventh scale tone - with a VII chord, which is a triad built on the seventh scale degree [and which fortunately doesn't serve too much of a purpose in traditional music, so forget you ever heard about it]).

You don't meet "seventh chords" too often in dance tunes either, but there are certain places where the melody seems to call for them and they can sound pleasant when used sparingly. The major seventh is I - III - V - VIIb (= means that the seventh degree is flatted), while the minor seventh is I - III - V - VII (= seventh not flatted).
Ex. 5:  D7 chord = I - III - V - VIIb = D   F#   A   C#b [ = C natural]
Ex. 6:  A7 chord = I - III - V - VIIb = A   C#   E   G#b [ = G natural]
Ex. 7:  Bm7 chord = I - IIIb - V - VII = B   D   F#   A

Seventh chords normally serve as "cadence" chords, i.e. the chord at the end of a tune just before it returns to the tonic. In most major key dance tunes, the cadence is V -> I (A to D, D to G, etc.); in minor key tunes, the cadence is VII -> I (D to Em, G to Am).  You never hear a VII7 chord used in Irish music.

2. "Altered" chords ("diminished" or "augmented" chords) are so rarely encountered in dance tunes that I won't spend any time on them here.


[a] Every tone in a scale can serve four functions in a chord:
- as the root :         D E F# G A B C# ----------------> major triad  D   F#  A
- as the third:         B C# D E F# G A ----------------> minor triad  B   D   F#
- as the fifth:          G A B C D E F#   ----------------> major triad  G   B   D
- as the seventh:     Eb F  G Ab Bb C D ---------------> "seventh" chord Eb   G   Bb   D

This means that in theory at least you can harmonize (= add a chord to) a melody note D in any of four ways.

But in Irish dance music, the harmony is not based on individual notes, or your backup players would go nuts. Imagine playing six chords to the six notes in the first measure of "Boys of Blue Hill"? Or eight chords to the eight notes in any measure of "Silver Spear"?

Instead dance music harmony is based on patterns and accents (as well of course as the note - chord relationship explained above). Working with these parameters, we can be reasonably certain that our attempts at harmonization will be, if not 100% correct, at least headed in the right direction.

[b] The key signature
The first step in analyzing a tune with the goal of harmonizing it correctly is to make sure we know what key the tune is in, which we can easily accomplish by checking its key signature. This knowledge will help us establish a priority of probabilities as to whether a particular note is likely to be a tonic/root, a third, a fifth, or a seventh of a particular chord.

For example, let's say we're analyzing a tune in the key of D. This means that any accented D note we find (see the discussion of Accented Notes below) has - let's say - a 60% chance of being the root of a D chord, a 20% chance of being V of a G chord, a 15% chance of being III of a Bm chord, and a 5% chance of being VII of an E7 chord. (These are all bogus percentages - I'm using them just to give you an idea what I'm talking about!)

There's also zero chance - given the key signature and the fact that we're working in a traditional context - that a Bb chord, a G minor chord, a B diminished chord, or any of the other chords that contain D will be correct. In this respect our knowing the key signature not only helps to establish the probability of what the correct chord will be, it also expedites the process of elimination so that we get rid of the "long shots" fairly quickly.

[c] Accented notes
As you already know, Irish dance music is arranged in beats, which in turn are created by the proper accenting by the musicians of certain notes in the tune.

A reel, for example, is in 4/4 time, which means that there are four beats (top figure) of quarter notes (bottom figure) in each measure or bar of the tune. In reality reels consist primarily of eighth notes, so the time signature of 4/8 would be closer to the truth. For a danceable beat to be established, the musician must stress the accent on notes 1, 3, 5, and 7.  In reels, the accent is fairly even.

The time signature for a jig is 6/8 (= six beats of eighth notes), but here again it's where the accent goes that makes the difference, and in jigs the accent is quite clearly on beats 1 and 4. For slip jigs (9/8), there are three accents per measure, on beats 1, 4, and 7. Slides are 12/8 and have four accents per measure, on beats 1, 4, 7, and 10.

In Chief O'Neill's day, most hornpipes were notated in 2/4 time, but today these tunes are in 4/4. As with reels, the accent goes on beats 1, 3, 5, and 7, but for dancers, hornpipes require special emphasis on beats 1 and 5.

Polkas noted in 2/4 have two accents per measure; those notated in 4/4 have four accents.

The relationship of all this accent information to the harmonic aspect of Irish music is as follows: when the time comes to decide what notes in a tune you want to consider adding chords to, you're going to focus on the accented notes only. In fact, you're not going worry about all of them either, for obvious reasons: even four chord changes per measure in a reel or a hornpipe would be too much.

So in those tunes, you'll focus on the notes that correspond to beats 1 and 5; in 6/8 and 9/8 jigs, the notes that correspond to beats 1 and 4 and 1, 4, and 7 respectively; in slides, on notes in position 1 and 7; in 2/4 polkas, on notes in position 1 and 3.

[d] Arpeggios
An arpeggio is basically a chord whose tones are played consecutively instead of concurrently. If I play piano or accordion or concertina or guitar, I have the option of playing all the tones in a chord at the same time, or I can play the tones as separate notes. Players of other instruments don't have the first option (double stops on fiddles or banjos notwithstanding), but certainly have the second.

The melodies in Irish traditional music are heavily based on arpeggios or "broken" chords, so that examination of the melody structure - the notes that follow the accented notes discussed above - will lead us further in the direction of deciding the correct harmonization.

For this procedure to be successful, it presumes that the musician doing the analysis is familiar with the triad structures outlined above, so that when he sees a series of eighth notes consisting of GECE he will recognize it as being a broken (arpeggiated) C major chord (= I: C, III: E, V: G)

This I find is a handy way of figuring out which notes correspond to which scale steps in any key.

If you really get ambitious, you can throw in the Roman numerals I mentioned before and get your chords too. I think this is very useful for us backup players who specialize in chord relationships!

Example, using the D major scale (two sharps - "Silver Spear", "Lark in the Morning")

1 note D I D chord
2 note E II Em chord (explanation below)
3 note F# III F#m chord (ditto)
4 note G IV G chord
5 note A V A chord
6 note B VI Bm chord (ditto)
7 note C# VII don't worry about this one!

When you start out with a major scale, some of the chords that you come up with - namely, the II, III, and VI - will always be minor chords. The reasons are pretty technical and have to do with neat stuff like "triadic intervals", which are interesting but not relevant to what I want to do here. (Same holds for the VII chord in a major scale.) If you want to pursue the matter, any basic music theory book from the library will tell you all you could possibly want to know (and more, much more).

Can you use this procedure with a minor scale? Sure, but the results come out a little differently!

Example, using the A minor scale (relative to C major, no sharps or flats - "Sligo Maid", "Cliffs of Moher")

1 note A I Am chord
2 note B II incomplete - like a VII in a major key
3 note C III C major chord
4 note D IV Dm chord
5 note E V Em chord
6 note F VI F major chord
7 note G VII G major chord

Notice: when you build harmonies based on a minor scale, the III, VI, and VII will always be major chords, while I, IV, and V will always be minor. (In the present discussion, disregard the fact that Irish minor keys are almost always played with the 6th scale degree sharpened [Aeolian mode]).

It's important to understand these relationships because the little "m's" that we're so familiar with in our chord symbols don't appear automatically when we build our harmony chart - we have to know when to be looking for them.

Now that you have all this good theory, let's move on to the tables I've made up that will I hope assist you in finding the appropriate chord to harmonize any given note. I realize that the choice of chords in Irish traditional or any music is in some respects a matter of taste. However, since my tastes in backup tend to be conservative ones, I have listed only the chords I consider to be appropriate to the task: you won't find any 7th chords, augmented or diminished chords,etc. These are all fine and wonderful harmonies in the context of George Gershwin or Duke Ellington, but I don't think they have a place in the harmonic accompaniment of Irish traditional music, and on that basis you won't find any listed here.

A reminder: the following harmonization suggestions apply to accented notes (i.e. the notes where the beats fall).


1. Key sig: TWO SHARPS
melody note D maj
possible chords
B minor
possible chords
D D, Bm, G Bm, D, G
E A, Em A, Em
F D, Bm, F#m Bm, D, F#m
G G, Em G, Em
A D, A, F#m F#m, A, D
B G, Bm, Em Bm, Em, G
C# A, F#m F#m, A


2. Key sig: ONE SHARP

melody note  
G maj
possible chords      
E minor
possible chords
G G, C, Em Em, G, C
A D, Am D, Am
B G, Em, Bm Em, G, Bm
C C, Am Am, C
D G, D, Bm D, G, Bm
E C, Em Em, C
F# D, Bm Bm, D


3. Key sig: THREE SHARPS

melody note A major
possible chords
F# minor
possible chords
A A, D, F#m F#m, A, D
B E, Bm Bm, E
C# A, F#m, C#m F#m, A, C#m
D D, Bm Bm, D
E A, E, C#m E, A, C#m
F# D, F#m, Bm F#m, Bm, D
G# E, C#m C#m, E



melody note C major
possible chords
A minor
possible chords
C C, F, Am Am, C, F
D G, Dm Dm, G
E C, Am, Em Am, C, Em
F F, Dm Dm, F
G C, G, Em Em, C, G
A F, Am, Dm Am, F, Dm
B G, Em G, Em


5. Key sig: ONE FLAT

melody note F major
possible chords
D minor
possible chords
F F, Bb, Dm Dm, F, Bb
G C, Gm Gm, C
A F, Dm, Am Dm, F, Am
Bb Bb, Gm Gm, Bb
C F, C, Am C, F, Am
D Bb, Dm, Gm Dm, Gm, Bb
E C, Am Am, C


scale degree any major = I relative minor = VI minor = I
1 I, IV, VI VI, I, IV I, IV, VI
2 V, II II, V VII, V
5 I, V, III V, I, III I, V, III

The chords are all numbered based on their relationship to the tonic (= root note) of the major key.

Remember: building from a major scale, the II, III, and VI chords are always MINOR; building from a minor scale, the III, VI, and VII chords are always MAJOR. Chords you don't have to worry about (unless you want to!): VII in major, II in minor.



Everyone even slightly familiar with Irish music knows about "modal" tunes ("Banish Misfortune" and "Rakish Paddy" are two examples).

While a musicologist might understand the word in a broader context than we do, all we as Irish musicians have to know is that in "modal" tunes most if not all of the accented 7th-degree-of-the-scale notes in the tune are flatted (i.e., the C# in the key of D now becomes C natural, the F# in the key of G now becomes F natural, and so on).

Harmonizing the "flatted" note in "modal" tunes is relatively simple: use either the chord that has the same name as the note name, or its relative minor.

key D modal: C# lowered to C natural: use either C or A minor
key G modal: F# lowered to F natural: use either F or D minor  

That's basically all there is to it. Again, the choice of chord will depend on your ear.   



[a] Major scales
The pitches of a major scale are arranged so that the "spaces" between adjoining pitches is as follows (W = whole step, H =
half step) starting at the first pitch: W , W , H , W , W , W , H

Example: D major scale = D, E, F#, G, A, B, C#, D'
D to E = whole step ; E to F# = whole step; F# to G = half step; G to A = whole step; A to B = whole step; B to C# =
whole step; C# , D' = half step

D    E    F#   G    A    B    C#    D'
---v----v----v----v----v----v-----v---,    W   W    H    W    W   W    H

Any major scale (i.e., beginning on any tonic note) will be constructed using exactly the same WWHWWWH relationship.
The relationship is what defines it as a major scale.

[b] Minor scales
 The minor scale is defined by a different arrangement of whole and half steps: W , H , W , W , H , W , W. The D minor
scale is thus: D, E, F, G, A, Bb, C, D'.

Notice the difference between the two scales:
major has F# and C#
minor has F (natural) and C (natural), plus Bb instead of B (natural)

I'll use another (crude) graphic to illustrate the relationship of pitches in a minor key:

D    E    F    G    A    Bb    C    D'
---v----v----v----v----v----v-----v---,    W    H   W   W    H    W    W

Again, this defining relationship applies regardless of what the tonic (= starting) note is.

As you know, the sounds of major and minor scales are quite different; the arrangement of whole and half-steps creates an emotional response in the listener that nobody fully understands (think of the difference between "Mason's Apron", key A
major, and "Star of Munster", key A minor, and you'll know what I'm talking about).

[c] "Modal" scales
I mentioned "modes" above and explained (or tried to) how a "modal" scale is formed. Since so-called modal tunes are not
uncommon in the Irish tradition, let's do the step analysis on the two modal scales most common in Irish music, namely the
mixolydian mode and the aeolian mode.

Here's the mixolydian mode, characterized by the lowered seventh, applied to the D major scale:

D    E    F#    G   A    B    Cn   D'
---v----v----v----v----v----v-----v---,    W   W    H    W   W    H    W

And the Aeolian mode, characterized by a sharped sixth, applied to the A minor scale:

A    B    C    D    E     F#   G     A'
---v----v----v----v----v----v-----v---,    W    H   W   W    W   H    W