Task: Question Generation
Input (English): Context : William C. Arthur (4 July 1830 -- 15 November 1886) was a Royal Navy officer who was the namesake of the English name for Lüshunkou, Port Arthur, which changed hands between China, Imperial Russia, Japan, and the Soviet Union between 1894 and 1945. 
Subject : William C. Arthur 
Relation : military branch
Output (English): What military branch did William C. Arthur belong to?