Hill grew up in Berkeley, Calif., and played for two seasons at UCLA. He made two appearances for the U.S. national team. He also played on the U-20 and U-23 national teams.
Hill joins a team that has 10 Brazilians, two Frenchman and an Angolan among its foreign contingent.
Vitoria SC played in the qualifying round of the 2008-09 UEFA Champions League but is only ninth in the Portuguese First Division with two games to play.