The war was fought primarily along the frontiers between New France and the British colonies, from Virginia in the South to Nova Scotia in the North. It began with a dispute over control of the confluence of the Allegheny and Monongahela rivers, called the Forks of the Ohio, and the site of the French Fort Duquesne and present-day Pittsburgh, Pennsylvania. The dispute erupted into violence in the Battle of Jumonville Glen in May 1754, during which Virginia militiamen under the command of 22-year-old George Washington ambushed a French patrol.