Fort Buchanan was a United States Army post founded in 1856 three miles southwest of present day Sonoita, Arizona in what is now called Hog Canyon. The fort was located on the east slope of the canyon and was under constant threat from Apaches. The dramatic increase in fighting with the Apache was initiated by the Lt "Bascom Affair" that was started near Sonoita. Lt Bascom and his patrol were based at Ft Buchanan. The post was officially abandoned in 1861 but during the American Civil War troops of the California Column occasionally manned the post. In February 1865 Apaches attacked and forced the small garrison to retreat.