March of the Meanies by The Beatles is an instrumental track from the soundtrack of their animated film 'Yellow Submarine.' The song's title refers to the 'Blue Meanies,' the antagonists in the film who symbolize negative and oppressive forces. The track uses a blend of eerie and whimsical instrumentation to evoke a sense of menace and conflict. The key themes revolve around the clash between good and evil, creativity, and the power of music and love to overcome hatred.