Noah was a Nephite city and land west of the river Sidon, near the city of Ammonihah. It had been the weakest part of the land until Captain Moroni fortified it, building forts and banks of earth for every city in the region round about; the city of Noah was made strong enough to exceed the strength of Ammonihah (Alma 49:12-15). Moroni expected that the Lamanites, frightened away from Ammonihah, would march against Noah as the weaker target, and so it happened.
The Lamanites retreated into the wilderness and marched toward Noah, their chief captains swearing an oath to destroy its people (Alma 49:13). They attacked at the place of entrance but were driven back and slain in great numbers. When they tried to dig down the banks of earth to gain an equal field, they were cut down by stones and arrows, and the ditches around the city filled with their own dead and wounded (Alma 49:20-22). More than a thousand Lamanites were killed, including all their chief captains, with no Nephite slain and about fifty wounded; the survivors fled into the wilderness and returned to the land of Nephi to report their loss to King Amalickiah (Alma 49:23-25).