Our Series on Territorial Formation takes us to the Arabian Peninsula, with the creation of the modern nation of Saudi Arabia.
While the Ottoman Empire took control of the shores of the peninsula around the 16th Century, they never fully controlled the rugged interior, which was still fundamentally tribal. Two major families were in dispute for the control of that land, the Rashidis, based in the Ha'il Region, and the Saudis, further South in Nejd. In 1891, the Saudis were defeated and the Rashidis controlled both regions, but in 1902, Saud retook Riyadh, the capital of Nejd, and created the modern Saudi State.
This was the beginning of a conquest that would see the Saudis control most of the peninsula over time: the Eastern oasis of Al Hasa was taken in 1913, the Rashidis of Ha'il were defeated in 1921, and Asir was taken from Yemen in 1923.
The crown jewel, though, was achieved in 1927 with the defeat of the Kings of Hejaz, on the Red Sea, who controlled the holy cities of Mecca and Medina. Nejd and Hajaz were ruled as separate kingdoms until 1932, when the Saudi ruler merged his possessions as the new Kingdom of Saudi Arabia.
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