HMS "Commonwealth", was a of the British Royal Navy. Like all ships of the class (apart from ) she was named after an important part of the British Empire, namely the Commonwealth of Australia. Armed with a battery of four and four guns, she and her sister ships marked a significant advance in offensive power compared to earlier British battleship designs that did not carry the 9.2 in guns. "Commonwealth" was built at the Fairfield Shipbuilding and Engineering Company, and was laid down in June 1902, launched in May 1903, and completed in March 1905.