Fort Arbuckle was created in 1850 to stop raids by Plains Indian tribes on immigrant trains headed west to California and on settlements of Choctaws and Chickasaws in Indian Territory. Captain Randolph B. Marcy was assigned the mission of selecting the site and constructing the fort, which would be named to honor the recently deceased General Matthew Arbuckle. The site was inside the boundary of the Chickasaw Nation and on the bank of the Washita River, 6 miles (9.7 km) west and 1 mile (1.6 km) north of the present town of Davis, Oklahoma. The overall size of the post was originally 12 miles (19 km) by 12 miles (19 km), allowing enough room for friendly tribes to camp under the protection of the post.