Hopalong Cassidy was a Western pulp fiction character whom actor William Boyd played in a number of early films to some success; in the 1930's, Boyd took over rights for the character and began starring in a number of lower-budget features under the new name. By the 1950's, Hopalong Cassidy was a clean-cut cowboy beloved by young boys who idolized him and tried to live by his Code of the West. Boyd's easy smile, gray-white hair, and black hat were familiar to millions of TV and movie viewers.
Hopalong Cassidy was probably the most merchandised actor/character of his era, and perhaps of all time. So much product was devoted to the cowboy, in fact, that two issues of a Hopalong Cassidy Merchandising Magazine were published in 1950, devoted to listing items licensed featuring Hoppy's image and/or name.
Few remember it today, but there was even an amusement park devoted to the character: Hoppyland operated on 80 acres in Venice, California, from 1951 to 1954.