The Venetian–Genoese Wars were a series of struggles between the Republic of Genoa and the Republic of Venice, at times allied with other powers, for dominance in the Mediterranean Sea between 1256 and 1381. There were four bouts of open warfare, in which the fighting between the two republics took place largely at sea. Even during periods of peace, incidents of piracy and other minor outbreaks of violence between the two trading communities were commonplace.