The community was named after the 15th President of the United States, James Buchanan. It is popularly known as “Redbud City” because of the many redbud trees that have historically lined city streets and the major approaches to the city. It has the St. Joseph River running through its borders. Buchanan has long been recognized as a Tree City USA by the National Arbor Day Foundation. The area was originally populated by Native Americans in places such as the Moccasin Bluff site, which was first settled in 1833 at the spot where McCoy Creek meets the St. Joseph River. The village of Buchanan was platted in 1842 and incorporated in 1858.

Today, the residents of Buchanan can enjoy beautiful nature with the Fernwood Botanical Garden, the St. Joseph River, and Mandron Lake. They can explore the arts with the Tin Shop Theatre and Buchanan Art Center. The history can be found throughout the township with such things as Pears Mill, a flour mill built in 1857 and using the water power of McCoy Creek, still stands and is open for visitors during the summer and other sites protected by the Buchanan Preservation Society.