Lieutenant Colonel Griswald is a US Army officer and Gus Griswald's father. He tends to address Gus as if he were a soldier in his squad, although it is clear that he is very fond of him. He had a rivalry with Naval Lieutenant Luke LaMaise.
Wife: Madge Griswald
Son: Gus Griswald
Friends: Miss Finster, Principal Prickly, Miss Grotke, Miss Lemon, Luke LaMaise (sometimes), TJ Detweiler, Vince LaSSao, Ashley Spinelli, Gretchen Grundler, Mikey Blumberg, Gus Griswald, Randall Weems and Menlo
Enemies: Earwin Lawson, Gelman, Conrad Mundy, Greg Skeens, Sue Bob Murphy, Lazy Kid, Chucko Kowalski, Jocko, Buster, Cheay, Koreo, Kurst the Worst and Luke LaMaise (sometimes)
Likes: Helping his son, punishing troublemakers, competing with Luke LaMaise, playing football and war against Luke LaMaise and teaching his son
Dislikes: Troublemakers, his son letting him down, losing the match, his son in trouble and troublemakers bullying Gus (especially Gelman)
- A continuity error; in his first appearance, Griswald introduced himself as a Marine officer. In later episodes, he was changed to being in the Army without explanation.