Short answers, pulled from the story.
Douglas Aircraft Company was founded by Donald Wills Douglas Sr. on the 22nd of July 1921 in Santa Monica, California, following the dissolution of the Davis-Douglas Company. It was reorganized under the Douglas Aircraft Company name on the 30th of November 1928.
The Douglas World Cruiser was a modified version of the DT torpedo biplane, built at the request of the U.S. Army Air Service to attempt the first circumnavigation of the Earth by air in 1924. Two of the four aircraft completed the journey, departing Seattle on the 6th of April 1924 and returning there on the 28th of September 1924.
Douglas Aircraft produced nearly 30,000 aircraft between 1942 and 1945. During the war the company's workforce grew to 160,000 people, and it ranked fifth among all U.S. corporations in the total value of wartime production contracts.
The Douglas DC-3 is a commercial transport aircraft that first appeared in 1936 and is often regarded as the most significant transport aircraft ever built. In military service it flew as the C-47 Skytrain, and British forces called it the Dakota.
By 1967, Douglas was struggling with production shortfalls, quality problems, cash flow issues, DC-10 development costs, and Vietnam War-related supply shortages. After nearly four years of talks, Douglas and McDonnell Aircraft Corporation merged on the 28th of April 1967 to form McDonnell Douglas Corporation.
Douglas Aircraft designed the S-IVB stage used in both the Saturn IB and Saturn V rockets, the vehicles that carried NASA's Apollo missions. The company also became the main contractor for the Thor ballistic missile program and the Skybolt air-launched ballistic missile in the 1950s-1960s.