'It's the Great Pumpkin, Charlie Brown' is based on the popular comic strip Peanuts created by Charles M. Schulz. The comic strip first appeared in newspapers on October 2, 1950, and quickly became a beloved staple in American culture. The animated television special, which aired in 1966, follows the adventures of Charlie Brown, Snoopy, and their friends as they prepare for Halloween and eagerly await the arrival of the Great Pumpkin. The special has since become a Halloween classic and continues to entertain generations of viewers.