I was gonna post this as is but I think some insight is in order:
This song, "Leave Her Johnny," is an old Irish sea shanty that was popularized by its inclusion in the video game Assassin's Creed: Black Flag. Johnny Collin's rendition of it is equally haunting.
You can appreciate the song as is, but knowing its history makes it that much better.
To the casual listener, one would reasonably assume that this song is about a sailor leaving his wife behind to go earn a living on the high seas. This is not the case. Rather, the "her" they're leaving behind is Ireland, and applied not just to sailors but also settlers and explorers.
This song is about overcoming homesickness to find a better life.