What was rin tin tin tin?

The first Rin-Tin-Tin was a German shepherd brought back to the United States from France after World War I by a serviceman named Lee Duncan. Duncan trained him as a police and war dog, then succeeded in getting him into movies, 28 of them, in most of which he was the star. He died in 1932. His son, Rin-Tin-Tin, Jr., also starred in several movies. Duncan tried dogs for war during World War II, and after the war, his Rin-Tin-Tins were prominent in the TV series "The Adventures of Rin Tin Tin" 1954-1959 .