It's an impossible question. And I am going to give a boring answer.
In the United States, I think that if we are including historical characters, the most famous figure is George Washington, the first president of the United States.
The capital city is named for him: Washington, D.C. Very confusingly, there is also a state, completely separate, called "Washington." There must be thousands of places named for him. His picture is on the one-dollar bill, the most common paper bill, and on the quarter. The main street in our town is named "Washington Street." There are more than twenty universities with "Washington" in their name. The US mountain claimed to have the "most extreme weather in the world" is Mount Washington. Washington is one of the four presidents whose faces are carved into Mount Rushmore. And so on, and so on, and so on.