Ramona, I think the series you remember is called -- oddly enough --
THE QUEST.  I remembered Perry King in something that sounded vaguely
familiar so I called a Perry King fan.  You sure have a good memory.
The show only played from Oct.22, 1982 to Nov. 19, 1982.  Like the
5 year mission, it was cut short.
 
Here is the premise: The ruler of the Principality of Glendora dies without
an heir leaving his land in the position of being gobbled up by France.
Research is done and FOUR possible heirs are discovered, all are
Americans.  The ruler wannabees must pass some 13th century test to
decide which one will rule Glendora.
 
Perry King..........Dan Underwood
Karen Austin........Carrie Welby
Noah Beery..........Art Hinley
Ray Vitte...........Cody Johnson