The Canadian Broadcasting Corporation has produced a series of programs based on Modern Publics: 1500-1700, a book by a group of scholars at McGill University. The program is podcast online.
Modern Publics looks at the concept of "public," available for all to see, a choice once decided only by men of rank.
From the description:
Matters of state, Queen Elizabeth I proclaimed to her subjects in 1559, were fit to be treated only by “men of authority” and conveyed only to audiences of “grave and discreet persons.” By the 18th century it had become meaningful to talk about public opinion as a sovereign power formed outside the state. What happened in the intervening years to make this revolution possible is the subject of this Ideas series.