HMS Blanche (H47) was a B-class destroyer built for the Royal Navy around 1930. During the Spanish Civil War of 1936–1939, the ship spent considerable time in Spanish waters, enforcing the non-intervention measures agreed by Britain and France. She was attacked, but not damaged, by Nationalist bombers in early 1938 and was subsequently transferred to the Home Fleet. Blanche was sunk by a mine in November 1939, becoming the first British destroyer lost to enemy action in World War II.

The A- and B-class destroyers were a group of 18 destroyers built for the Royal Navy during the late 1920s, with two additional ships built for the Royal Canadian Navy. The British ships were divided into two flotillas of eight destroyers, each with a flotilla leader.