The birth in greatness and luxury of one of the richest court families seemed to provide Prince Felix Yusupov Count Sumarokov-Elston Jr. a life filled with the brilliance of the Russian imperial court. But the fate that befell the youngest son of Princess Zinaida Yusupova and Count Felix Sumarokov-Elston was much more unexpected. This book is the first complete documentary biography of Prince Felix Yusupov ever published in the world, based on previously unpublished extensive Yusupov archives stored in Russia, France and the UK. The biography was based on 14,000 unknown letters from the Yusupov family, the diary of Princess Zinaida Yusupova, unpublished memoirs of Prince Felix Yusupov-Art. and the memories of their family and friends.