Williams began his revolutionary career as a Lieutenant Colonel of Orange County Minutemen:
British Colonel Donald McLeod began marching 1,600 Loyalists from Cross Creek, North Carolina, toward the coast, where they were supposed to rendezvous with other Loyalists and Redcoats at Brunswick, North Carolina. When Commander Richard Caswell (1729-89) and some 1,000 Patriots arrived at Moores Creek Bridge, near present-day Wilmington, ahead of the British Loyalists, Caswell positioned his troops in the woods on either side of the bridge, awaiting the British with cannons and muskets at the ready.
The British learned of the Patriot troops at Moores Creek in advance, but, expecting only a small force, decided to advance across the bridge to attack. The British Loyalists shouted, “King George and Broadswords!” as they moved across the bridge; they were swiftly cut down by a barrage of Patriot musket and cannon fire.
This was a critical victory, which effectively broke the Crown's control and influence in North Carolina. It also sent a strong message to those still "undecided" about which side to fight on. But even though the various district Minutemen thrashed the loyalists (including the much-feared Scots), they were deemed too expensive and disbanded in favor of local militias. Shortly thereafter Williams was commissioned as a full Colonel and commanded the 9th North Carolina Regiment in the Continental Army. They fought and froze through the Winter of 1777 in Valley Forge, and were disbanded in 1778. Later that year, as he was serving as a delegate to the Continental Congress, he wrote this letter to Robert Burton: