Which of these Disney productions was released earlier--The Three Caballeros or The Monkey's Uncle?  
The Three Caballeros
Title: Yale Gracey
Passage: Yale Gracey (1910 – September 5, 1983) was a Disney Imagineer, writer, and layout artist for many Disney animated shorts, including classics such as "The Three Caballeros" and "Fantasia".  Gracey joined the company in 1939 as a layout artist for "Pinocchio".  He designed many of the special effects for the Pirates of the Caribbean and Haunted Mansion attractions at Disneyland.  The Haunted Mansion character Master Gracey was named in homage to him.  Gracey retired from the company on October 4, 1975.
Title: The Three Caballeros
Passage: The Three Caballeros is a 1944 American live-action animated musical package film produced by Walt Disney and released by RKO Radio Pictures.  The film premiered in Mexico City on December 21, 1944.  It was released in the United States on February 3, 1945 and in the UK that March.  The seventh Disney animated feature film, the film plots an adventure through parts of Latin America, combining live-action and animation.  This is the second of the six package films released by Walt Disney Productions in the 1940s, following "Saludos Amigos" (1942).
Title: The Monkey's Uncle
Passage: The Monkey's Uncle is a 1965 Walt Disney production starring Tommy Kirk as genius college student Merlin Jones and Annette Funicello (Who was a member of the mouseketeers from The Mickey Mouse Club) as his girlfriend, Jennifer.  The title plays on the idiom "monkey's uncle" and refers to a chimpanzee named Stanley, Merlin's legal "nephew" (a legal arrangement resulting from an experiment to raise Stanley as a human); Stanley otherwise has little relevance to the plot.  Jones invents a man-powered airplane and a sleep-learning system.  The film is a sequel to the 1964 film "The Misadventures of Merlin Jones."
The Monkey's Uncle The Three Caballeros