Lady Cynthia Blanche Mosley, nicknamed "Cimmie", was a British aristocrat, politician and the first wife of the British Fascist politician Sir Oswald Mosley.

The British Union of Fascists (BUF) was a British fascist political party formed in 1932 by Oswald Mosley. Mosley changed its name to the British Union of Fascists and National Socialists in 1936 and, in 1937, to the British Union. In 1939, following the start of the Second World War, the party was proscribed by the British government and in 1940 it was disbanded.