The Hashemite Kingdom of Hejaz was a state in the Hejaz region of Western Asia that included the western portion of the Arabian Peninsula that was ruled by the Hashemite dynasty. It was self-proclaimed as a kingdom in June 1916 during the First World War, to be independent from the Ottoman Empire, on the basis of an alliance with the British Empire to drive the Ottoman Army from the Arabian Peninsula during the Arab Revolt.

The Hejaz is a region that includes the majority of the west coast of Saudi Arabia, covering the cities of Mecca, Medina, Jeddah, Tabuk, Yanbu, Taif and Baljurashi. It is thus known as the "Western Province", and it is bordered in the west by the Red Sea, in the north by Jordan, in the east by the Najd, and in the south by the Region of 'Asir. Its largest city is Jeddah, which is the second-largest city in Saudi Arabia, with Mecca and Medina, respectively, being the fourth- and fifth-largest cities in the country.