In the 19th C. San Antonio was a training site for the African-American Cavalry Soldiers given this animal name
In the late 19th century Native Americans began calling the African-
American men, ... Training for the 28th Cavalry position involved artillery training 
in rifle and ... Got Their Name  About the Buffalo Soldiers  The Ninth and Tenth 
Cavalry... [DOC] [TLE] Who were the buffalo soldiers?