The name was chosen in 1996 from the results of a poll conducted by the Baltimore Sun. Poe wrote this, one of his most famous poems, while living in Baltimore back in the 1830s. The teams mascots are even named Edgar, Allan, and Poe!
This was after the Cleveland Browns moved to Baltimore. They decided to change the name, and Cleveland's new team has the Browns name. For the 2 seasons before that, Baltimore was home to a Canadian Football League team. They were called the Colts before being sued by the NFL, and then changed their name to the Stallions. When Baltimore finally got another NFL franchise, the Stallions moved to Montreal and became the Alouettes.
More facts about the Ravens and their history.