This is a really cool song, and it has a great rhythm. Did everyone know that it was on the soundtrack of Assassin's Creed IV: Black Flag? (video game)

I mention this because my husband and I really took a shine to the shanties sung by the crew during the game, and since we often play Renaissance Festivals, we had a good deal of musical/geekery overlap amongst our listeners. So we decided to record a selection of the songs from the soundtrack for a new album. We were pretty sure all of the songs were traditional, and leafing through my Hugill's has bourne me out - but of course we have this one hang-up, we can't seem to find if anyone wrote this one! Even checking the credits on the official Assassin's Creed soundtrack it's pretty vague, and doesn't even identify any songs as traditional. Can anyone help me out on this?