July 1 - 1690 - The Battle of the Boyne
When William III of England, Scotland, and Ireland took his throne in 1688, he had done so at the invitation of leaders in England bothered by the birth of a son to the recently converted Catholic King James II. So William, Dutch defender of Protestantism and husband of James' daughter Mary, easily took the throne alongside his wife. Yet James' flight to France proved only a respite, as he began planning an invasion of England from Ireland. Backed by the French King Louis XIV and the Catholic gentry in Ireland, James had a formidable force. William met him on the River Boyne with a multinational, Protestant army. The Battle itself was rather simple, as William outmaneuvered James with a small flanking move by one detachment of troops. William was able to launch his troops across the river, slowly pushing back his enemy. Then, when it looked like a counterattack could stall William, James himself fled the field. With his victory, William established his rule, as well as Protestantism and Constitutional Monarchy in Britain. From that moment, the Battle of the Boyne would be a great symbol of the conflict between Protestant Unionists and Irish Nationalists in Ireland.