This map is part of a series of 18 animated maps showing the history of The Middle East since the beginning of the 20th century.
In the early 20th century, the Arabian Peninsula was a vast desert region, home to a number of small Bedouin States based on large tribal groups which were constantly fighting with each other. During the 18th century, one of these groups, the Saudi family, succeeded to uniting Arabia and promoting a strict form of Islam, the Wahhabite doctrine.
Following the invasion by Muhammad Ali in the 19th century, the Sauds were scattered but in 1901 the young Abdelaziz Ibn Saud set about re-establishing the ancient State of his ancestors. Leaving Kuwait, where he was born, he captured first Riyadh and then the regions of Najd and of Hassa.
In 1915, the war led the British to make alliances in the Peninsula. They recognized Ibn Saud’s conquests in Arabia but preferred to support his main rival, Sharif Hussein of Mecca, as leader of the Arab revolt against the Ottomans.
In 1918, war broke out between Ibn Saud and Sharif Hussein. Ibn Saud gradually extended his authority over the Southern, and later the Northern, tribes. This led to several conflicts with the British, but in the end, he recognized the Mandates, after negotiating several border changes.
As soon as London withdrew its support for Sharif Hussein, Ibn Saud attacked and took control of the Hejaz in 1925.
In 1926, Ibn Saud was now King of Hejaz, Sultan of Najd and Master of the Holy Places, and succeeded in imposing Wahhabism as part of the official Sunnite Islam.
In exchange for recognition of his independence, he maintained friendly relations with Great Britain and renounced his claims for control over the Gulf Emirates. In 1932, he merged all his territories into the Kingdom of Saudi Arabia and, two years later, captured and annexed the Yemenite province of Asir.
Oil fields were discovered in the Arabian Peninsula in the 1930s. To counter the powerful sons of Hussein, now Kings of Iraq and Jordan, Ibn Saud turned his back on the English and offered the first concessions for drilling to American companies. Commercial oil wells began operating in 1939.