In 1521, the Portuguese Empire allied with Hormuz and seized Bahrain from the Jabrid ruler Muqrin ibn Zamil, who was killed during the takeover. Portuguese rule lasted for around 80 years, during which time they depended mainly on Sunni Persian governors. The Portuguese were expelled from the islands in 1602 by Abbas I of the Safavid Iran, which gave impetus to Shia Islam. For the next two centuries, Persian rulers retained control of the archipelago, interrupted by the 1717 and 1738 invasions of the Ibadis of Oman. During most of this period, they resorted to governing Bahrain indirectly, either through the city of Bushehr or through immigrant Sunni Arab clans. The latter were tribes returning to the Arabian side of the Persian Gulf from Persian territories in the north who were known as ''Huwala''. In 1753, the Huwala clan of Nasr Al-Madhkur invaded Bahrain on behalf of the Iranian Zand leader Karim Khan Zand and restored direct Iranian rule.