He had a long affair with the famous ballerina Mathilde Kschessinska , who had previously been the mistress of Nicholas II .
Grand Duke Sergei remained a bachelor living at his father palace in the imperial capital .
Grand Duke Sergei had a long affair with the famous ballerina Mathilde Kschessinska , who had previously been the mistress of Nicholas II .
Grand Duke Sergei remained a bachelor living at his father palace in the imperial capital .