On September 9, 1775, the NC Provincial Congress appointed William Bryan as a Lt. Colonel under Col. Needham Bryan in the Johnston County Regiment of Militia. Lt. Col. William Bryan was with his regiment at the battle of Moore's Creek Bridge on February 27, 1776.

On April 22, 1776, the NC Provincial Congress appointed William Bryan as Colonel/Commandant over the Johnston County Regiment of Militia, replacing Col. Needham Bryan who had resigned his commission.

In January of 1777, William Bryan was appointed Brigadier General over the New Bern District Brigade of Militia, replacing Richard Caswell, who was sworn into office as the State's first governor. Brig. Gen. William Bryan led the New Bern District Brigade of Militia at the battle of Briar Creek, GA on March 3, 1779. He resigned his commission soon after this battle on April 27, 1779, and returned to civilian life.

William Bryan was "re-activated" as Colonel over the Johnston County Regiment of Militia for the battle of Guilford Court House on March 15, 1781. Soon after that battle, he returned to civilian life.

William Bryan was a delegate to the Third Provincial Congress of August 1775 in Hillsborough. He was elected to represent Johnston County in the NC House of Commons 1778-1779.

William Bryan, the son of Needham Bryan and Anne Rombeau, was born on October 31, 1724 in Bertie County, NC. He married Elizabeth Smith c.1744, and they had nine known children - Lewis, William M., Arthur, Elizabeth, Hardy, Blake, Esther, Susannah, and John. One source asserts that he and his son Lewis were poisoned by one of his slaves and he died at his home in Johnston County on November 28, 1781. Other sources indicate that it was not this man.