In the 1960s and 1970s, the Milton Bradley Company produced not only simple games for children, but also more serious games for adults and older kids. The firm's American Heritage series included games which recalled important battles in American history. And the firm produced other strategy games on many subjects, outside of this series. In the 1980s and 1990s, the firm utilized strategy game mechanics from the Warhammer series of games produced in the United Kingdom by Games Workshop. The games were similar but did not use the Warhammer name.