The Sabaean Kingdom came into existence in at least the 11th century BCE. The four major kingdoms or tribal confederations in South Arabia were Saba, Hadramout, Qataban, and Ma'in. ''Saba’'' () is thought to be biblical Sheba and was the most prominent federation. The Sabaean rulers adopted the title Mukarrib generally thought to mean ''unifier'', or a ''priest-king'', or the head of the confederation of South Arabian kingdoms, the "king of the kings". The role of the Mukarrib was to bring the various tribes under the kingdom and preside over them all. The Sabaeans built the Great Dam of Marib around 940 BCE. The dam was built to withstand the seasonal flash floods surging down the valley.