Is it C sharp or C nat?
Thanks
Frank
Insufficient data. What key are you playing/singing it in, and which of the various melody notes would you be referring to? (I.E. whereabouts in the tune are you thinking of?)
Hi Frank.
The version I know is in the key of G which would mean a C nat. However the tune does not use that note.
Based on the final cadence of both the A part and B part, that would be more usually regarded (and notated) as E minor, not G major.
But yes, the tune is pentatonic, missing the 4th and 7th of the relative major scale. Which means that in either GMaj/Emin or DMaj/Bmin, the nature of the C is moot.
I play the tune using a C natural,I dont understand written music or theory, 7ths 4ths or anything mentioned above and not sure on abc’s but in my world it would start like this
EGAAA GAccd cded cAGEG EGAAA GAccd cded dcAAA
egee dcddd cdedcAGEG cBAAA GAcc d cded cAAA
You’re playing it in CMajor/Aminor pentatonic. So naturally (pun intended) you’re using C natural. 
The one I’m playing I think is in G but then again music theory is something I’m lacking. When I play it on the D whistle C sharp seems to play better for me. On the UP I can go either way.
Frank
What is the very last note of the tune when you play it (corresponding to the word “Down” in the lyrics)? That will tell us what key you’re playing in.
I play it in either B minor or A minor, both go equally well on the uilleann pipes.
B minor starts:
d C# B
A minor starts:
Cnat B A
I don’t play it in E minor
G F# B
but I just tried it and there ain’t any C in it. Well you can put in a passing tone between B and d and to me is sounds like it should be natural.
BTW it’s a common hymn tune called KINGSFOLD.
The hymn Amazing Grace sounds fantastic sung to this tune, rather than NEW BRITAIN.
Brown Colleen
(Star of The County Down)
Near to Banbridge Town, in the County Down
One morning in July,
Down a boreen green came a sweet coleen,
And she smiled as she passed me by;
Oh, she looked so neat from her two white feet
To the sheen of her nut-brown hair,
Sure the coaxing elf, I’d to shake myself
To make sure I was standing there
Oh, from Bantry Bay up to Derry Quay,
And from Galway to Dublin Town
No maid I’ve seen like the brown collen
That I met in the County Down.
As she onward sped I shook my head
And I gazed with a feeling quare;
And I said, says I, to a passer-by,
“Who’s the maid with the nut-brown hair?”
Oh, he smiled at me, and with pride says he,
“That’s the gem of Ireland’s crown,
She’s young Rosie McCann from the banks of the Bann,
She’s the Star of the County Down.”
I’ve tavelled a bit, but never was hit
Since my roving career began;
But fair and square I surrended there
To the charms of young Rose McCann.
I’d a heart ot let and no tenant yet
Did I meet with in shawl or gown,
But in she went and I asked no rent
From the Star of the County Down.
At the crossroads fair, I’ll be surely there
And I’ll dress in my Sunday clothes
And I’ll try sheep’s eyes, and deludhering lies
On the heart of the nut-brown Rose.
No pipe I’ll smoke, no horse I’ll yoke
Though with rust my plow turns brown,
Till a smiling bride by my own fireside
Sits the Star of the County Down.
A…So I guess I was wrong thinking it was G.
Yep. 
You’re playing it in CMajor/Aminor like accordionstu. So C-natural is your ticket to bliss.
Cheers for this Tommy, I wonder how many people sang to it when you posted the lyrics, I did 
, but Can you change Bambridge to Banbridge? I used to go fishing there as a lad and also met my first ex wife from there, a lovely place and I am sure there are some sweet colleen’s there, but in hindsight, I should have stuck to the fishing 
Ya did. You just should have thrown one back. 
Is there one particular setting most common with this tune?
Don’t think so. Because it’s pentatonic, the tune sits nicely in C, G, D or A (that is, Am, Em, Bm or F#m). And because it’s a song, you might be called on to play it in any of those keys to match the vocal range and preferences of a singer.
Bejasus, begorrah, and possibly whack-fol-the-diddle-o! I am Irish, and that’s too much Paddywhackery for me
Don’t care if it’s C# or C, if anyone asked me to play along with this nonsense they’d have to buy me a drink first.
m.d.
Hmmmmmmmm……. OK 
I will buy the first round.
About various settings to the melody, I should point out that there’s nothing particularly “Irish” about it.
It appears to be one of many old melodies common throughout Britain and Ireland, and since the melody has been around so long you’ll find many variants of the melody, and many different songs sung to it.
As I said it also occurs in hymnody where the tune is called KINGSFOLD. In hymnody the tunes have their own names (independent of the names of the hymns, hymns being sets of words) and tune names are customarily rendered in all caps.
You’ll come across this old tune both in 4/4 time and 3/4 time. 4/4 is more widespread and seems to be the older way. KINGSFOLD is in 4/4.
Anyhow strictly speaking there is no “tune” called The Star Of The County Down, that being a song set to a very old tune.
Here is a wonderful setting of KINGSFOLD, as normally played in churches. It is always listed as an old “English folk tune”.