The "pulpit" that Shakespeare refers to was the Rostra, the speaker's platform in the Forum.
Perhaps because England didn't have anything like the Forum, the center of all the most important business, political, ceremonial, and celebratory activies in Rome, Shakespeare uses words that would his audience could relate to: "market-place" for the Forum, and "pulpit" for the Rostra.
The Rostra of Caesar's time
