Uncivil War Birds (1946)

"Civil war breaks out between the states, but the Stooges dont know which side their state will be on. Moe and Larry join the Union, Curly the Confderates. Last appearance of Stooge supporting actor John Tyrrell."

The stooges are civil war soldiers who are constantly changing uniforms to avoid the opposing armies. Eventually they decide to be loyal to the south, but remain disguised as Union soldiers. Curly is detected as a spy, but Moe and Larry prevent his execution. The boys escape with a secret map and marry their three southern belles.