Al-Aḥsā'

Al-Ahsa is an oasis about sixty kilometres inland from the Gulf, where springs rise out of the desert and feed vast date plantations. Its old name was Hajar, and the oasis includes the towns of Hofuf and Mubarraz. The Qarmatians, a radical Shia sect, made it the capital of their independent state around 899, and about 1000 it was among the largest cities in the world. After their fall in 1077 a series of Arab dynasties ruled the oasis, the last of them the Jabrids, who also held the islands of Bahrain until the Portuguese seized them in 1521.

Suleiman the Magnificent brought Al-Ahsa under Ottoman sovereignty in 1550, and the oasis became the Ottoman province of Lahsa, usually a vassal of the sultan. Around 1670 the Banu Khalid, a local tribal confederation, expelled the Ottomans and ruled the oasis from Hofuf. In the 1790s the Saudi emirate of Diriyah took it, and in 1818 Egyptian troops under Ibrahim Pasha entered Hofuf but left the following year. The Banu Khalid returned to power, and the Saudi emirate of Najd retook the oasis in 1830.