A major period of westward expansion took place in the United States during the first half of the 19th century. The task of protecting the settlers from the Native American tribes that inhabited the Great Plains fell to the US Army, and to do this they constructed a network of permanent forts and temporary camps. By 1867, there were 116 forts and camps on the frontier, and 36 of these were on the northern and central plains. This title takes a close look at how and why these particular forts were built, their design and defensive features, and details the pivotal role they played in the settlement of the American West.