The Cleveland Browns were originally going to be called the Cleveland Oilers. In 1998, owner Bud Adams wanted a nickname change. In Nashville, there is a full-scale replica of the Parthenon and other Greek influences and the city was already known as “the Athens of the South.” Adams chose "Titans" from a list of suggestions to reflect heroic qualities for the Titans.
Here is the history of the teams logo
Here is the history of the teams logo