Antamont was a terrestrial planet in the Expansion Region, close to Murkhana. It was covered in forests, deserts, jungles, tundras, plains, and oceans. Despite that, it was populated by only several thousand people spread across the planet.
In 19 BBY near the end of the Clone Wars, the world became a major battleground between the Galactic Republic and the Confederacy of Independent Systems. Led by Jedi Master Plo Koon, the 123rd Division of the Grand Army of the Republic was ordered to defend the planet from an attack by the Separatists. They were aided by the Antamont Militia, a small planetary security force. The battle was a victory for the Republic. The Jedi wanted to continue to protect the world from attacks by the CIS, but him and his men were needed elsewhere, so he just had the 123rd drill sergeants train the Antamont militia for about a week, before they had to depart.
Galactic Civil War
After hearing of the formation of the Galactic Empire, as well as Emperor Palpatine's execution of Order 66 and the Great Jedi Purge, the centralist government of Antamont was outraged. Being strong supporters of the Jedi Order, they provided sanctuary to any Jedi trying to escape the Empire. At least three Jedi were known to have went into exile there. The Antamont militia supported the Alliance to Restore the Republic, and acted as their Antamont garrison.
In 1 ABY, following the Empire's defeat at Murkhana, two defectors, an Imperial Inquisitor named Mitsuko Souma and an Incinerator trooper named IC-8947, were forced to land their stolen Azanlak-class cargo transport on the planet due to it running low on fuel. The Antamont militia heard of them on the HoloNet, and captured the two defectors. By order of Alliance High Command, they were sent to Hoth, were the Rebel base was located.