Allen Buchanan (December 22, 1876 – January 12, 1940) was an officer in the United States Navy and a Medal of Honor recipient for his role in the United States occupation of Veracruz.

Citation: For distinguished conduct in battle, engagements of Vera Cruz, 21 and 22 April 1914.

His duties required him to be at points of great danger in directing his officers and men, and he exhibited conspicuous courage, coolness, and skill in his conduct of the fighting.

Upon his courage and skill depended, in great measure, success or Failure.

Downes, engaged in the important, exacting and hazardous duty of patrolling the waters infested with enemy submarines and mines, in escorting and protecting vitally important convoys of troops and supplies through these waters, and in offensive and defensive action, vigorously and unremittingly prosecuted against all forms of enemy naval activity.