The Sioux armies are mainly composed of Cavalry units. They have the strongest cavalry units of all of the Native American civilizations, but only mediocre infantry. One of the most unique and important ability of Sioux is that they do not need to build houses; they already have 200 population cap from the very beginning of the game. Their houses are replaced by Teepees, which, instead of increasing population, increase hitpoint and attack of nearby units.
Their armies consist of mostly cavalry, as their infantry are mediocre and do not possess artillery, but the armies are quite balanced, too. Ranged infantry can be countered by Axe Riders, Dog Soldiers, and Tashunke Prowlers. Heavy infantry can be beaten with Dog Soldiers and Rifle Riders. Cavalry can be destroyed with Bow Riders and Rifle Riders, and artillery can be countered with any unit. Buildings can be destroyed by the use of the Fire Dance or any cavalry with high siege damage.
"The Sioux Nation is made up of three geographically different divisions of peoples who speak varying dialects of the Siouan language: the Lakota, Dakota, and Nakota. In the language of Sioux, the names Lakota, Dakota, and Nakota mean “friends.” The Sioux lived on the Great Plains of the western United States and survived primarily by hunting. Their favorite game was the American bison, or buffalo, which provided food, clothing, and shelter.
They were excellent horsemen, famed for their ability to fire bows and guns accurately while riding at full gallop. Experts at horse breeding, they owned horses both fast and clever. These animals were considered extremely valuable, and some warriors owned hundreds of them. They were used not only for war, but also as a medium of exchange.
One of history’s most renowned Sioux warriors was Sitting Bull, known also as Tatanka Yotanka (1831-1890). Born in the territory now known as South Dakota, he was revered as a Sioux principal chief, medicine man, and prophet. Sitting Bull led Native resistance against U.S. government attempts to take over tribal lands, which included his involvement in the Battle of the Little Bighorn. After spending several years in Canada with his followers, Sitting Bull returned to the U.S. under a government amnesty program. Sitting Bull's leading war chiefs were Crazy Horse and Gall."