The site reported Tuesday (Feb. 19) that Oswalt will play a history buff who clashes with Leslie (Poehler) when she tries to change the incredibly outdated Pawnee Charter.
His objection stems from the belief that life was better in 1817 when the Indiana town was first founded, and that the people who wrote the charter were geniuses whose words should never be altered.
Poehler confirmed to HitFix.com in January that she would be directing the 19th episode of season (airing this spring), marking the second time the actress will be stepping behind the camera after writing and directing the critically-praised Season 4 episode "The Debate."
Oswalt's TV credits include nine seasons as Spence Olchin on "King of Queens," recent guest spots on "Two and a Half Men," "Justified" and "Burn Notice," and an upcoming role in Aaron Sorkin's "The Newsroom."
"Parks and Recreation" will air back-to-back episodes this Thursday, Feb. 21 that will include Leslie and Ben's (Adam Scott) much-anticipated wedding.