From Magicpedia, courtesty of Genii Magazine:

Senor (Charles) Mardo (June 8, 1895 - March ?, 1976) was the stage name of Medardo Lonzano, born in Havana Cuba.
He performed as a full-time professional, close-up, club, and stage magician from the 1940s through the 1960s. Mardo was born to a Cuban father and French mother and spoke over six different languages. He moved to the United States around 1912 and became a citizen around 1921. He married Lynne Castel in 1922.

By 1954 he had won 22 magic trophies. Mardo’s Egg Bags were made by his wife, Lynne, who also performed the trick, which was described in Mardo’s first book, Routined Magic. Mardo spent his later years in New York City and was often found at Lou Tannen's Magic shop helping young magicians. His final book, a sequel to Routined Magic was lost in the fire that gutted the offices of Tannen's.

It has also been reported that he was a spy who worked for the U.S. Government on missions in Cuba. His wife, Lynne (born in Little Rock, Arkansas on January 31, 1917), was a master puppeteer and made her own marionettes. She would perform her puppet show and Mardo would perform his Magic Show as a complete evening package, since 1941.

It was reported in the Genii 1976 April that he passed away that year.