In Greek mythology, the Titanomachy was a 10-year war between the Titans and the Olympian gods to decide who would become the ruler of the cosmos. The leaders of the Titans in the battle was Atlas while the leader of the Olympians was Zeus. The Titans had their base on Mt. Othrys and the Olympians had their base on Mt. Olympus. It took place shortly after Zeus freed his siblings from the stomach of their father Cronus. Zeus then went to Tartarus to release the Hekatonkheires (hundred-handed ones) and Cyclopes to assist him in the battle. Zeus promised that whoever would side with him would be rewarded while those who side with the Titans would be punished. The Cyclopes made Weapons for the gods such as the Ligtening bolt for Zeus, Trident for Poseidon, and the Helm of Darkness for Hades while the Hekatonkheires threw giant rocks at the Titans. After 10 long years, the Olympians were successful in defeating the Titans. Zeus then locked all of the Titans away. Atlas was forced to hold up the celestial sky, The Hekatonkheires guarded the gates of Tartarus that most of the Titans were locked in. Prometheus and Themis were on Zeus' side so they were not punished. Some sources say that eventually Zeus released the Titans except for Atlas.
One of the main sources of information on the Titanomachy was called the Titanomachia by Eumelus of Corinth, however this work was lost. Another source of information about the Titanomachy comes from the Theogony by Hesiod but it is said that these two sources differed on the war.