The Goddesses Al-Uzza, Al-Lat and Menat formed a triad in pre-Islamic Arabia. They were widely worshipped: from Nabatean Petra in the North to the legendary Kingdoms of Arabia Felix in the South, including Saba, known as region known as Sheba in the Bible; as far east as Iran and Palmyra; and the three of them were very popular Goddesses in Mecca at the time of Muhammad.
Hubal (Arabic: هبل) was a god worshipped in pre-Islamic Arabia, notably at the Kaaba in Mecca. His idol was a human figure, believed to control acts of divination, which was in the form of tossing arrows before the statue. The direction in which the arrows pointed answered questions asked of the idol. The origins of the cult of Hubal are uncertain, but the name is found in inscriptions from Nabataea in northern Arabia (across the territory of modern Syria and Iraq). The specific powers and identity attributed to Hubal are equally unclear. The three goddesses were sometimes said to be his daughters.
"The Four" is Harry Turtledove's invention. This designation is not generally used for these deities.
The Four in "Occupation Duty"
The Arabs traditionally worshiped four gods: Aluzza, Allat, Manah and Hubal - known collectively as "The Four". Moabites had support from the Arabs in their ongoing guerrilla war against the Philistinians and their graffiti showed it with slogans such as "The Sword Buddha and the Four with Chemosh!". This also indicated support from the Turks of Babylonia and their fanatical religion of Sword Buddhism.
- See e.g.: Atlantis and Other Places, pg. 240, HC.