The Shakespeare of Advertising
Phineas Taylor Barnum, "master entrepreneur and colossal hoaxster ... credited with a genius for bunkum, hokum, hooey, hoopla and ballyhoo" is front and center in a "Circus and The City: New York 1793 - 2010" exhibition. In his 9/21/12 NYT article Glenn Collins cites LaVahn G. Hoh, a circus historian and professor of drama, with annointing Barnum as "The Shakespeare of Advertising."
Certainly Barnum did not invent the circus, but he crafted a traveling model that lives to this day. He knew to appeal to the whole family, showcased talents that came with the waves of immigrants, and debuted Jumbo the Elephant -- at 13-feet tall, he was billed as "the children's giant pet."
One poster from 1875 has Barnum's portrait encircled by circus animals, with no other proclamation than three simple words: "I Am Coming". I think Barnum would have thrived on Twitter, but perhaps his most lasting legacy is to THINK BIG.