From www.coopersjd.com:
Death Valley Days is a long-running American radio and television anthology about true stories of the old American West, particularly the Death Valley area.
It was created in 1930 by Ruth Woodman and ran on radio until 1945. It ran from 1952 to 1975 as a syndicated television series.
The 558 television stories, which had different actors, were introduced by a host. The longest-running was "The Old Ranger" from 1952-1965, played by Stanley Andrews...
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... Following the departure of Andrews, Ronald Reagan became the host.
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...Death Valley Days is, judging from sheer number of episodes broadcast, by far the most successful syndicated television Western, the most successful television Western ever in the half-hour format, and arguably the most successful syndication of any genre in the history of the U.S. television market (Baywatch had a larger international market among U.S.-produced syndicated programs).
Presented by:
Stanley Andrews (1952-1965)
Ronald Reagan (1965-1966)
Robert Taylor (1966-1969)
Dale Robertson (1969-1972)