Answer:
It took a litte bit but here is what has been provided me by the Idaho State Historical Society:No citation, but the YMCA has a great story about how it got its name.
http://ycampidaho.blogspot.com/2010/02/how-horsethief-got-its-name.html
Answered on:
Thursday, May 29, 2014 - 10:15 AM MDT