A County Older Than the State. Montgomery County is the fourth largest of the 67 counties in the state of Alabama. The County's population, according to the 2000 census was 223,510. Hernando DeSoto and his troops passed near Montgomery, Ala., in the autumn of 1540. Settlers first began to populate the area in the early 1800s and the county of Montgomery was created by an Act of the Legislature of the Mississippi Territory on December 6, 1816. Montgomery County was named in memory of Major Lemuel P. Montgomery, of Virginia, who fell at the Battle of Horseshoe Bend in 1814. The City of Montgomery, which became the county seat in 1822, was built on the side of the Indian town Ikanatchati, which means red ground, and Towasa on a high red bluff known to Alibamu Indians as Chunnaanaauga Chatty.