During the height of tabletop board wargames in the 1970's, there were two major manufacturers and a lot of little ones. SPI was one of the majors. What was the OTHER MAJOR, a company started in 1954: now a subsidiary of Wizards of the Coast, and sometimes referred to by the "AH" in its logo? Games they created included Midway, Third Reich, and Blitzkrieg.
Avalon Hill