Okita Sōji
"Okita" (沖田) was his family name; "Sōji" (総司) was his given name; "Fujiwara" (藤原) was his family clan (the surname of his ancestors); "Kaneyoshi" (房良) was his jitsumei, a formal given name (like a middle name for gentlemen equivalent). It is unclear whether Okita changed his name to "Okita Sōji Fujiwara no Kaneyoshi" in 1863 or in 1862 (or less likely, in 1861.) There is a theory that he changed his name to Sōji because some people around him called him "Sō-Ji" (short for Sōjirō.) Other than his full name, he could be referred as "Okita Sōji" or "Okita Sōji Kaneyoshi". In writing, he was sometimes referred as "Fujiwara no Kaneyoshi" (formal name used in writing) or "Okita Kaneyoshi" (like the "initials" for his full name.)