Prince William was formed in 1730 and named by the General Assembly after the second son of George II. Prince William was made the Duke of Cumberland in 1726 when he was five years old, so he was all of nine years old when honored by the name of the new county. Cumberland County and Cumberland Gap are also named after him.
King George II and his wife Caroline liked Prince William far better than his older brother Frederick, but Prince William still missed a chance at becoming king after his Frederick died in 1751. Instead, Parliament and the King's ministers chose the late Frederick's oldest son, George, to become King George III.
Since Fredericks son (Prince William's nephew) was only 13 years old at the time, his mother Augusta was prepared to serve as regent if necessary until the new Prince of Wales turned 18. However, George II lived nine more years until 1760, when young George III was crowned. His 39-year old uncle remained the Duke of Cumberland.
Prince William was trained initially to be Lord High Admiral of the British Navy, but he preferred the army. During the War of Austrian Succession on the continent, he was wounded in the Battle of Dettingen. Today's Episcopal Parish of Dettingen in Prince William County is named after that British victory.1
In 1745, back in Britain, Prince William won a smashing victory at Culloden that stopped an uprising led by "Bonnie Prince Charlie" and his Scottish troops. This eliminated the threat from the rival House of Stuart (sons of King James II) to the legitimacy of the English kings from the German state of Hanover (the "House of Windsor"). Prince William treated the defeated Highlanders so harshly that he earned the name "Butcher of Culloden." In addition, the winning British called him "Sweet William," but the losers called him "Stinking Billy 2."
Prince William's military reputation was destroyed in one of the maneuverings during what the Virginians referred to as the French and Indian War. Prince William signed the Treaty of Kloster-Zeven in 1757 with the French, after his father King George II directed him to negotiate a way out of the situation without losing the English army on the continent - or losing the Hanover territory. The English Parliament was furious over the failure to fight and at least distract the French on the continent. Prince William ended up serving as his father's scapegoat and resigned in disgrace from the army 3.
along the Prince William County shoreline, Confederates managed to control the Potomac River between October 1861-March 1862
Source: Frank Leslie's Illustrated History of the Civil War, Birds-Eye View of the Burning of a Confederate Schooner on Quantico or Dumfries Creek, Potomac River, on the Night of October 11th, 1861, By Lieutenant A. D. Harrell and a Detachment from the Potomac Flotilla (p.282)
Dumfries (above) was chartered on the same day as Alexandria in 1749, using the same street names
Source: Prince William County Historic Preservation Division, Historic Perspectives (Fall 2016)
Prince William County in 1901
Source: Library of Congress, Prince William County in 1901 (by William H. Brown, 1901)
new construction in the Town of Occoquan includes high-priced townhomes on the waterfront
Prince William County owns the baseball stadium used by the minor league team, the Cannons
Source: Historic Prince William, PWC Stadium Complex