Alexander Anderson Jr., the cartoon mastermind that created Rocky & Bullwinkle, has died.

He passed away Friday at a nursing home in Carmel, California at the age of 90 due to complications from Alzheimer’s disease.

He got his start in the 1940s as an apprentice for his uncle, Paul Terry, the legendary cartoonist whose Terrytoons produced Mighty Mouse and Heckle and Jeckle.

Their most famous and enduring creation was a clever flying squirrel, Rocket J. Squirrel, and his dimwitted pal, Bullwinkle J. Moose, who lived together in the fictional town of Frostbite Falls, Minnesota.

Treez : I watched this show a little bit as a kid. The animation sucked and the show wasn’t really all that good. But I do remember it, and cartoons were good even when they sucked.