 Many Williamite troops at the Boyne, including their very effective irregular cavalry, were Ulster Protestants, who called themselves "Enniskilliners" and were referred to by contemporaries as "Scots-Irish".These "Enniskilliners" were mostly the descendants of Anglo-Scottish border reivers and large numbers of these reivers had settled around Enniskillen in County Fermanagh.The opposing armies in the battle were led by the Roman Catholic King James II of England (VII of Scotland) and Ireland and, opposing him, his nephew and son-in-law, the Protestant King William III ("William of Orange") who had deposed James the previous year.