On the night of 6 July Abraham Duquesne escorted Patrolling 5 fireships to the mole of the harbor , where the Spanish galleys were abandoned GiveUp , and set fire Damaging to them .

It began Process_start with a dispute over control of the confluence of the Allegheny River and Monongahela River called the Forks of the Ohio , and the site of the French Fort Duquesne in Pittsburgh , Pennsylvania .