The longest running soap opera in broadcast history, Procter & Gamble's (P&G's) The Guiding Light, premiered on radio in 1937. Although recognized as one of the many soaps developed by the legendary Irna Phillips, a 1946 lawsuit ruled that a former writer, Emmons Carlson, share credit for its creation. The veteran soap's logo, a rotating lighthouse beacon, was an apt metaphor for its significance as a guidepost in the cultural lives of generations of fans and for the genre itself. Over the decades, Guiding Light evolved into a paradigm model for the melodramatic excesses of soap opera, both influencing, and being influenced by, its imitators and successors. Within the liberating parameters of its world, it was frequently a ground-breaker, daring to dramatize previously taboo topics, and through its sheer longevity, has permeated American popular culture.

Reverend John Ruthledge (Arthur Peterson) served as the program's central character for many...