I've read this thread pretty thoroughly and don't think anyone has mentioned these three-- perhaps not the greatest-- many of those have already been mentioned.

This by Robert Burns:

LOGAN BRAES
Robert Burns, 1793

O Logan, sweetly didst thou glide
That day I was my Willie's bride,
And years sin syne hae o'er us run
Like Logan to the simmer sun.
But now thy flowery banks appear
Like drumlie winter, dark and drear,
While my dear lad maun face his faes
From far frae me and Logan braes.

Again the merry month of May
Has made our hills and vallies gay;
The birds rejoice in leafy bowers,
The bees hum round the breathing flowers;
Blythe Morning lifts his rosy eye,
And Evening's tears are tears o' joy:
My soul delightless a' surveys,
While Willie's far frae Logan braes.

Within yon milk-white hawthorn bush,
Amang her nestlings sits the thrush:
Her faithfu' mate will share her toil,
Or wi' his song her cares beguile.
But I wi' my sweet nurslings here,
Nae mate to help, nae mate to cheer,
Pass widow'd nights and joyless days,
While Willie's far frae Logan braes.

O, wae upon you, Men o' State,
That brethren rouse in deadly hate!
As ye make monie a fond heart mourn,
Sae may it on your heads return!
Ye mindna' mid your cruel joys
The widow's tears, the orphan's cries;
But soon may peace bring happy days,
And Willie hame to Logan braes.

Originally called Logan Braes and slated for publication in Scottish Airs.However, it was deemed too inflammatory for its anti-war message and was not published until 1800 in "Works".

I may have found this in the DT or on a Burns web site. Don't remember.

And this, which I learned from the second Silly Sisters album-- lyrics (I think) from Maddy Prior's site?:

BLOOD AND GOLD / MOHACS

On rides a captain and 300 soldier lads
Out of the morning mist and thro' the silent snow
Whistling gaily rides the captain at their head
Behind him soldier boys sadly weeping go
O lads of mine weep no more
You are gone to kill and die

For when you took my gold and swore to follow me
You sold away your lives and your liberty
No more you'll till the soil, no more you'll work the land
No more to the dance you'll go and take girls by the hand
O mother weep for your son
He is gone to kill and die

You'll weep, you'll die by the keen edge of the sword
You'll all go in the fire there'll be no hiding place
O mother hear the drumbeat in the village square
O mother that drums for me to go for a soldier there
Mothers sisters wives, weep for us
Marked as Cain we lie alone

MY SON JOHN

My son John was tall and slim
He had a leg for every limb
But now he's got no legs at all
For he run a race with a cannonball
With me roo rum rar, faddle diddle dar
Whack faddlle liddle with me roo rum rar.

Oh were you deaf, were you blind
When you left your two fine legs behind
Or was it sailing on the sea
Lost your two fine legs right down to the knee
With me roo rum rar etc.

Oh I was not deaf, I was not blind
When I left my two fine legs behind
Nor was it sailing on the sea,
Lost my two fine legs right down to the knee
With me roo rum rar, etc.

For I was tall, I was slim
And I had a leg for every limb,
But now I've got no legs at all,
They were both shot away by a cannonball.
With me roo rum rar, etc.

I think many of the traditional songs were composed by those left behind. I think it was perhaps more politically dangerous to speak to the bigger issues back then than now-- go back several hundred years and you see a very different social picture. If we aren't careful to protect those freedoms we may turn back the clock...