 In 1755 he participated as a volunteer aide in the ill-fated expedition of General Edward Braddock, where he distinguished himself in the retreat following the climactic Battle of Monongahela.He served from 1755 until 1758 as colonel and commander of the Virginia Regiment, directing the provincial defenses against French and Indian raids and building the regiment into one of the best-trained provincial militias of the time.He led the regiment as part of the 1758 expedition of General John Forbes that successfully drove the French from Fort Duquesne, during which he and some of his companies were involved in a friendly fire incident.