Finnair was established in the year 1923 as Aero O/Y. It entered into Finnish trade register on December 11th, 1923. Finnair's first flight flew on March 20th, 1924 from Helsinki to Tallinn. The airline saw half of its fleet requisitioned by Finnish Air Force during World War II. In the year 1946, Government of Finland acquired a major stake in the company. It re-established services to Europe on November 1st, 1947 and in 1953, it branded itself as Finnair. In the year 1961, Finnair joined jet age with the addition of Rolls-Royce Avon-engine Caravelles to their fleet. In 1961, it bought Douglas DC-8, a U.S. made jet. Finnair joined Oneworld Alliance in 1999.