From Muppet Wiki

Christopher Columbus (ca. 1451-1506) was an Italian navigator widely credited with the discovery of America. Columbus gained financing for the voyage through the queen of Spain. Some time around 1492, he was also accosted by a journalistic amphibian, Kermit the Frog, who interviewed him on his plans for the voyage for a News Flash sketch on Sesame Street. Intriguingly, the Muppet Columbus claims his intent is to discover America, and not seek a spice route to the Indies as is widely accepted.

Columbus Day is celebrated on the second Monday in October in the United States. A town in Ohio also bears his last name. The explorer was not a known influence on Columbo, however.