As we mentioned in our "In a Nutshell" section, Robert Burns was The Poet of Scotland. In fact, in many ways, he still is today. His poems are Scottish through and through, and a big part of that stems from his own sense of national identity. The guy really wanted to preserve the Scottish heritage of folk songs, ballads, and other rural oral literature from the countryside.
And this poem is no exception to that rule. With its mentions of the sea, the rocks, the sun, we might as well be wandering the Scottish moors in search of folk songs ourselves. It's hard to imagine anyone other than a rural farmer or shepherd singing this tune, though we're sure many an urbanite has tried.