Bronisław Piotr Piłsudski (1866-1918) was a Polish cultural anthropologist who made an outstanding research on Ainu ethnic group which at the time inhabited the Sakhalin Island, but currently only inhabits the Japanese island of Hokkaido.
Piłsudski was involved in an undercover socialist group and was sentenced by tsarist Russian authorities to 15 years long hard labour exile on the Sakhalin Island.