Lydia Lopokova, Baroness Keynes (born Lidia Vasilyevna Lopukhova, Russian: ??´??? ????´?????? ??????´??; 21 October 1892 – 8 June 1981) was a Russian ballerina famous during the early 20th century.
Lopokova was born into a family of ballet dancers, and trained at the Imperial Ballet School.
She toured with the Ballets Russes in 1910, and moved to the United States soon after.
Lopokova married the renowned English economist John Maynard Keynes in 1925, and was also known as the Lady Keynes.
She largely disappeared from public view after Keynes's death in 1946, and spent her remaining years in Sussex.