Persian Gulf flooding of the basin started 15,000 years ago due to rising sea levels of the Holocene glacial retreat. This inland sea of some is connected to the Gulf of Oman in the east by the Strait of Hormuz; and its western end is marked by the major river delta of the Shatt al-Arab, which carries the waters of the Euphrates and the Tigris. In Iran this is called "Arvand Rood", where "Rood" means "river". Its length is , with Iran covering most of the northern coast and Saudi Arabia most of the southern coast. The Persian Gulf is about wide
Piracy in the Persian Gulf the British to further their agendas in the Persian Gulf. Indian historian Sugata Bose maintains that while he believes the British colonial accounts of piracy were self-serving, he disagrees with Al Qasimi's thesis that piracy was not widespread in the Persian Gulf region. Davies argues that the motives of the Al Qasimi tribe in particular may have been misunderstood and that it cannot be definitively stated that they were pirates due to issues of semantics. J.B. Kelly comments in his treatise on Britain and the Persian Gulf that the Qasimi are undeserving of their reputation as pirates, and goes on