"Tex" Thompson struck it rich in the oil fields of Texas and decided to travel the world. Dring his travels, he often found himself solving mysteries. Eventually, he and his freind Bob Daley worked in a major American city on the staff of Special Prosecuter Mahoney, helping him fight organised crime.

Thompson resigned to undertake a special war relief mission, and left for abroad on the Angelis, a mercy ship carrying supplies for the needy. He caught a sabatuer working for a foreign power on board, but was unable to prevent the ship from being blown up. Thomson was believed dead. But instead, he was found more dead than alive, by a Portugese fishing boat, and regained his strength in Lisbon. Thompson vowed to wage war on against enemy spies, sabatuers and fifth columnists. Returning to America, he took the Masked Identity of Mister America and captured Pratt, the leader of the sabotuers responsible for the Angelis' destruction.

As Mister America, tex saw himself fighting for the spirit of America. he whistled "Yankee Doodle" and left behind red, white and blue striped feathers as his trademarks. His friend, Bob Daley, teamed up with him as the comical costumed crimefighter Fatman.

Mister America joined the wartime All Star Squadron. President FDR named Mister America "Americommando" and had him undergo intensive training to become a special commando and secret agent behind enemy lines. The Americommando was assigned to masquerade as Nazi officers, sabotage Axis plans and aid axis victims. Americommando operated successfully in both Europe and the Pacific, but it is not known whether he survied the end of World War Two.