The M's are the last names of two men. The first man is Forrest E. Mars, Sr., founder of the Mars Company. The other M stands for Murrie, as in Bruce Murrie, son of long-term Hershey president...
Initials of Forrest Mars Sr. and R. Bruce Murrie.
After the rights were purchased by them in 1939, they had to reintroduce them to the domestic market with a different name because there...