Rin Tin Tin or Rin-Tin-Tin was a male German Shepherd born in Flirey, France, who became an international star in motion pictures. He was rescued from a World War I battlefield by an American soldier, Lee Duncan, who nicknamed him "Rinty". Duncan trained Rin Tin Tin and obtained silent film work for the dog. Rin Tin Tin was an immediate box-office success and went on to appear in 27 Hollywood films, gaining worldwide fame. Along with the earlier canine film star Strongheart, Rin Tin Tin was responsible for greatly increasing the popularity of German Shepherd dogs as family pets. The immense profitability of his films contributed to the success of Warner Bros. studios and helped advance the career of Darryl F. Zanuck from screenwriter to producer and studio executive.

The German Shepherd, also known in Britain as an Alsatian, is a German breed of working dog of medium to large size. The breed was developed by Max von Stephanitz using various traditional German herding dogs from 1899.