What is Don Draper's birth name?

Don Draper’s birth name is Dick Whitman. The revelation is one of Mad Men’s central mysteries: Don is not the identity he was born with, but an assumed identity taken during the Korean War.

Whitman served alongside Lieutenant Donald Draper. After the lieutenant died in a fuel-tank explosion, Dick switched their dog tags and allowed others to believe he was the dead officer. He returned to the United States as Don Draper and eventually built a new life in New York advertising.

The secret explains much of the character’s guarded behavior, ambition, and fear of exposure. His new identity helps him escape his impoverished and traumatic childhood, but it also leaves him emotionally divided. “Donald Draper” is therefore not his birth name; it is the identity he adopted. Roger Sterling and Pete Campbell are colleagues, not alternate names for him.