In 1901, Abdul Aziz ibn Saud and the rest of the Al Saud clan were in penniless exile in Kuwait. With some small support from the Emir of Kuwait, Ibn Saud selected 40 of his best warriors and set out to conqueror Riyahd from the rival Rashidi. Living on ghazu (tribal raiding for food, water, and loot), Ibn Saud gathered a force of about 100 on his journey, and in November stormed into Riyadh. But the Rashidi learned of the attack and fell back to the Al Mismak fort. With no siege weapons and no way to isolate the fort, Ibn Saud retreated back into the desert.
Ibn Saud and his men stayed there for 50 days in order to lull the Rashidi into complacency. Then with 15 of his best warriors, he snuck back into the town on the last night of Ramadan. He seized the Rashidi governor’s mansion, but he wasn’t there. His wives said that he spent his nights at the fort but came back in the morning.
On the morning of 15 January 1902, the governor walked across the plaza back to his mansion and Ibn Saud and his men attacked. The Rashidi governor raced back to the fort but the Saudis grabbed him just as he reached the gate. His men attempted to pull him in as the Saudi’s tried to pull him out. Finally, Ibn Saud pulled his scimitar and chopped off the governor’s extended arm that the defenders were pulling on. The governor died and soon the leaderless Rashidi surrendered the fort.
Arabs flocked to Ibn Saud’s banner, and by the time of World War One, the Saudis would be the most powerful Arab tribe on the peninsula. With the help of British after the Treaty of Darin in 1915, Ibn Saud joined the war against the Ottomans. After the war he set about conquering the other rival tribes of the peninsula and spread his peculiar form of Islam, Wahhabism, which neither the Rashid nor the Ottomans practiced. Wahhabists believe in a strictly literalist Koran (and hence abrogation). In 1932, Ibn Saud united the Kingdoms of Nejd and Hejaz into the Kingdom of Saudi Arabia