XIII may refer to:13 (number) or XIII in Roman numerals 13th century in Roman numerals XIII (comics), a Belgian comic book series by Jean Van Hamme and William Vance XIII , a 2003 video game based on the comic book series XIII , a remake of the 2003 video game XIII: The Conspiracy, a TV miniseries based on the comic book series and game of the same title XIII: The Series, a 2011 TV series based on the comic book series and miniseries XIII , 1998 XIII , 2003 XIII , 2018 Factor XIII, a clotting factor inside the coagulation cascade Rugby league, still often known as just XIII in France due to the name Rugby once being forbidden for the league code