The British ship the Princess Royal was a 774 ton iron hulled screw steam boat built in Glasgow, Scotland. She was trying to run the Union blockade of Charleston, South Carolina on January 29th 1863 when she was captured by the USS Unadilla. She was purchased from the Philadelphia Prize Court in March 18th 1863 and refitted as a cruiser. Commissioned May 29th 1863, she was placed under the command of Melancthon B Woolsey.
The USS Princess Royal was sent to the Gulf of Mexico in June 1863. Her first Union action was an engagement against Confederates in Donaldson, Louisiana on June 28th 1863. While serving off the Texas coast between 1863 and the end of the war in 1865, she captured or wrecked a number of blockade runners. The Princess' last capture was the CSS Anna Sophia in February 7th 1865 in Galveston Bay, a cotton loaded schooner.
Following the end of the war the Princess was sold, and she became a merchant steamer. She was sunk January 10th 1874 off the Cape Fear, North Carolina.