First National arose as a response to the rising power of Paramount, whose rapid growth in the business of production and distribution of movies gave independent theater owners the idea to make movies themselves, as opposed to buying them from studios. In 1917, a man named Thomas L. Tally founded First National Exhibitors' Circuit, which was in essence a merger between 26 major theater chains across the United States, giving the new company 600 theaters right out of the gate. It quickly signed deals with silent era superstars Charlie Chaplin and Mary Pickford, among other independent producers, to produce films to be shown in First National theaters. The investment quickly paid off, scaring Adolph Zukor of Paramount into entering the exhibition business himself, but not before trying (and failing) to take over First National itself. This would start a chain reaction that resulted in most of the major film studios owning their own theater chains until the late 1940s.
In 1919, with the expansion into full-on distribution, the company reorganized as Associated First National Pictures, Inc., with its 5,000 member theaters being part of a subsidiary called Associated First National Theatres, Inc. It reorganized again in 1924 as First National Pictures, Inc., which signified its move into actual in-house production, and built a studio lot in Burbank just two years later.
As First National grew, another movie studio was rapidly expanding: Warner Bros.. With the release of The Jazz Singer and the subsequent start of the sound era, Warner Bros. was seeing its profits skyrocket, and in 1928, it bought the majority of First National's shares. This formed a combined entity known as Warner Bros.-First National based in First National's studio lot, though the two would remain their own separate brands for the next seven years, with Warner Bros. generally handling musicals and other such lavish pictures while First National handled crime films and other stories based primarily in modern times. Ultimately, First National was officially absorbed into Warner Bros. in 1936, though the opening titles of most WB features would retain the Warner Bros.-First National credit for the next two decades.
Since First National was at its peak during the Silent Age, the studio is largely forgotten outside of film buffs, not helped by the abysmal track record of film survival during that time, resulting in much of its silent filmography being lost for ever. Still, it certainly left its mark in film history. WB kept its theaters until the Paramount decree forced them to divest the chain, and the former First National lot remains in their possession to this day, famously being used as the setting of the 90s hit cartoon Animaniacs, and among its surviving films are some of the most famous films ever made, ranging from the Charlie Chaplin masterpiece The Kid to Stop Motion special effects landmark The Lost World. Much of this library is owned by Warner Bros., though many of them (especially the silents) have fallen into the public domain.