Short answers, pulled from the story.
Walt Disney first asked to buy the film rights to Mary Poppins in 1938. He traveled to London to meet author P.L. Travers at her home in Chelsea and kept trying until he finally succeeded in 1961.
Filming took place between May and September 1963 at the Walt Disney Studios in Burbank. A special camera fitted with a prism filtered sodium vapor light to create accurate mattes for the production.
Julie Andrews accepted the role while three months pregnant because Disney promised to postpone filming until after birth. She had just been passed over for My Fair Lady when Jack L. Warner chose Audrey Hepburn instead.
Richard M. Sherman and Robert B. Sherman composed all music and lyrics for the film. They took inspiration from Edwardian British music hall traditions and Irwin Kostal arranged and conducted the score for Buena Vista Records.
The film premiered on the 27th of August 1964 at Grauman's Chinese Theatre in Los Angeles. It received thirteen Academy Award nominations which was a record for any Walt Disney Studios release.
Mary Poppins earned $31 million in theatrical rentals within the United States and Canada during its initial run. Worldwide rentals reached $44 million in total across all territories with net profits of $28.5 million reported by Cobbett Steinberg.