Tonto was a native american of either Comanche or Potawatomi tribes who found John Reid after he almost died from gunshot wounds caused by an ambush of Texas rangers by a gang of outlaws who they were in pursuit of. Tonto nursed him back to health and together they joined to fight for the innocent of the old west. Tonto of course is one of the very few who know the Lone Ranger's true identity.
He helped the Lone Ranger because of the Lone Ranger's strength of character and his will to help those in need. Tonto is starting to slowly to realize the importance of friendship and helping others.
Tonto helped the Lone Ranger catch and train Silver the white stallion. Silver only responds to commands from the Lone Ranger or Tonto just like Scout (Tonto's horse).
Jay Silverheels played Tonto for many seasons on The Lone Ranger television series.
Michael Horse played Tonto for the Legend of the Lone Ranger movie in 1982.
Disney did a movie about the Lone Ranger but they made the mistake of casting Johnny Depp as Tonto and it was filmed like the pirate movies from Disney. It was a BIG let down for the fans and the native american community because they did not use a native american actor for Tonto.