where is it headquartered?
Amarillo, Texas
American Quarter Horse Association
The American Quarter Horse Association (AQHA), based in Amarillo, Texas, is an international organization dedicated to the preservation, improvement and record-keeping of the American Quarter Horse. 
what is easy jet? American Quarter Horse when was it born? 1967 is it a member of any association? Yes, he was one of only two horses to have been a member of the American Quarter Horse Association Hall of Fame as well as being an offspring of members. when was it founded? March 15, 1940
wiki:20026693
American Quarter Horse Association [SEP] Introduction
The American Quarter Horse Association (AQHA), based in Amarillo, Texas, is an international organization dedicated to the preservation, improvement and record-keeping of the American Quarter Horse. The association sanctions many competitive events and maintains the official registry. The organization also houses the American Quarter Horse Hall of Fame and Museum and sponsors educational programs. The organization was founded in 1940 in Fort Worth, Texas, and now has nearly 234,627 members, over 32,000 of whom are international.