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Iranian Ziyarid ruler
Gilanshah (Persian: گیلانشاه) was the last ruler of the Ziyarid dynasty from ca. 1087 to 1090. He was the son and successor of Keikavus. Little is known about Gilanshah; his kingdom was invaded by the Nizari Ismaili state in 1090, ending Ziyarid rule in Tabaristan.