Francis Connolly Shannon (27 July 1874 – 1 February 1959) was an Irish actor and writer.

A stage actor and silent film pioneer, Shannon made his screen debut in 1913's The Artist's Joke.

He later appeared in dozens of films through the mid-1920s, including The Prisoner of Zenda (1913) and Monsieur Beaucaire (1924).

Shannon then returned to the stage until beckoned back to Hollywood in 1931 and played a few substantial supporting parts, including Captain McTavish in Warner Bros.' Torchy Blaine series from 1937 to 1939, but he is most fondly remembered as the brilliant scientist Dr. Alexis Zarkov in the three Flash Gordon serials starring Buster Crabbe between 1936 and 1940.

[citation needed] Shannon died in Hollywood, Los Angeles, California, at the age of 84.