It was the unnamed religion at the time it was practiced by the people living in the region between Mediterranean Sea and Jordan River. As mentioned in Torah and Bible, the followers of this religion were enemies of Israelites. It was a polytheistic religion with EI as their supreme deity.
It was the conquest be Israel over the region and the religious pressure from Israelites that became the reason of the demise of this religion.
Atenism: Popular in Egypt, this monotheistic religion was introduced by Pharaoh Akhenaten. The god worshipped under this religion was Aten. Previously, the religion incorporated the old deites in it, but rejected them later.
(Courtesy: Religions Reviews)
It was the restrictive nature of Atenism that that made Egyptians leave it and go back to their older faith. After the death of Pharaoh Akhenaten, the religion faded away completely.
Manichaeism: It was founded in 3rd century AD by Mani, a Persian. The motive of the religion was combining world’s all religions like Zoroastrianism, Buddhism, and Christianity. Mani earned a large number of followers who used to spread his popularity across the globe, but the religion lost its popularity in the Middle Ages.
The main reason of the decline of this religion was its persecution by the Chinese Government, and the ancient Roman government.
Ashurism: Somewhat similar to the ancient Babylonian religion, Ashurism involved the worship of Ashur instead of Marduk. It was a polytheistic religion with around 20 important deites who were worshipped. There are some legends and myths in Ashurism which resemble that in Bible.
It ended in fifth century BC when the country of Assyria was destroyed.