The article is devoted to the battle on the river Boyne (July 1, 1690) – one of the largest battles of the War of the League of Augsburg and the largest battle in the history of Ireland. The conflict was caused by a clash between two crowned rivals – James II Stuart, who was overthrown during the “Glorious Revolution” of 1688–1689 in England, and Prince of Orange – statholder of the Netherlands, who seized the British throne and proclaimed himself King William III of Britain.