With Saudi Arabia we are back to the great Arab Revolt (see Jordan) and, of course, along with the Arab participants, T.E. Lawrence and a cast of assorted Brits.
Lawrence arrived in the area in the autumn of 1916 and already by December he had brought ships of the Royal Navy’s Red Sea Patrol to help fend off an Ottoman attack on the port of Yanbu, now in Saudi Arabia. In January 1917, the Royal Navy again helped Arab forces, this time in their capture of Wejh, with assistance that included a Royal Navy landing party. And 1917 also saw Lawrence and other British officers help with the Arab campaign against the strategically vital Damascus–Mecca Hejaz railway.
By 1918, the British and the French were stepping up support for the Arab rebels with more advisers being sent, plus substantial amounts of weaponry, including some heavy weapons. In the period after the Turkish defeat in the First World War, Hussein became established as the King of the Hejaz, a region bordering the Red Sea. Subsequently, Ibn Saud took control from Hussein and became king. In 1927, we signed the Treaty of Jeddah, recognising him as ruler of the Hejaz and Nejd, and in 1932 Ibn Saud declared the Kingdom of Saudi Arabia, with himself as king.