The lyrics of the song commemorate King William III of Orange's victory over James II at the Battle of the Boyne in 1690, part of the Williamite War in Ireland.
Modern historians also agree that this conflict, otherwise known as the Glorious Revolution and played out in Scotland as well, was the conclusion of the English Civil War of 1642–1651[1] Indeed, King James II as a very young Duke of York was present with his father Charles at the Battle of Edge Hill in 1642.
At the climactic scene of C. S. Lewis's novel That Hideous Strength, when protagonists are preparing for a dangerous fateful encounter with their enemies, the character MacPhee, an Ulster Protestant, is shown humming "The Boyne Water".
He had to flee Ireland to avoid prosecution for murder, and emigrated to Georgia, where in time he became a successful planter and the master of Tara.
[4] Many American versions of the traditional folk song "Barbara Allen" use a tune related to "The Boyne Water".