MMario is correct that this poem is from THE PIRATES OWN BOOK, in the back. Most people assume that it's an 19th century parlor room creation rather than the work of an actual pirate or sailor. There is no tune or composer indicated but it does work well with a minor tune such as "Down, Derry Down", i.e., "Blue Mountain Lake."

My own revision of this poem looks like this (I could never sing the phrase "powder room key" without giggling):

From Pirates Own Book © 1924
Adapted by Charlie Ipcar © 1993
Tune: "King John & the Abbot of Canterbury"
also known as "Blue Mountain Lake"
Key: Dm(7/Gm)

Pirates Own Song


Dm----------------------------C/Dm/Am
Hoist our flag to the mast, 'tis dark as the grave,
------Dm—C---Dm/Gm-------Am
Or the death which we bear, as we sweep o'er the waves;
---------Dm----------------------Am
Have the decks cleared for action, the gun crews prepared,
----Dm--------------------------C Dm/Am
The boarding-axe sharpened, the cut-lass-es bared.

Chorus

Dm------------C-----Dm/Am/Dm
And 'tis down, down; sink them all down!

Have the great guns run out, then bring unto me,
For the last of my duties, the gun powder key;
I'll never lower this black flag we bear;
If the sea be denied us, we'll fly through the air!

Chorus

To share lies the plunder, from our last prey,
'Tis mine to divide; 'tis yours to obey;
I claim not a portion; I ask but for mine –
A toast to our prize – one cup of red wine!

Chorus

Now some fight for riches; some fight for fame:
The first I despise; the last's but a name;
I fight for vengeance! I love to see flow,
At the stroke of my saber, the blood of my foe!

Chorus

I strike for the memory of long-vanished years:
Of a fair maiden lost, of a family in tears;
I come in a flash, as lightning from above,
And chase o'er the waves to the battle I love!

Chorus

Arrghhh!
Charley Noble