Which 1943 Disney short introduced Chip and Dale as a pair of mischievous chipmunks?

Private Pluto introduced Chip and Dale as a pair of mischievous chipmunks in 1943.

In the short, Pluto is assigned to guard an army camp, while two chipmunks interfere with his duties. The unnamed chipmunks display the contrasting behavior that later defined the duo: they cooperate against Pluto, exploit his temper, and turn ordinary objects into tools for comic sabotage.

Chip and Dale did not initially have all the visual and personality traits associated with their later appearances. Their names and designs became more firmly established in subsequent cartoons, including shorts made specifically around their rivalry with Pluto and Donald Duck.

The pair is often confused with the later television franchise Chip ’n Dale: Rescue Rangers. That series gave them new costumes and an investigative premise, but the characters originated in theatrical Disney cartoons. Private Pluto therefore represents the beginning of their shared screen history.