A member of an unknown species, Yoda was born on an unknown planet in 896 BBY. He and a Force-sensitive friend were discovered and trained by the Jedi Master N'Kata Del Gormo. By the age of 100, Yoda achieved the rank of Jedi Master.
Yoda's skill earned him a place on the Jedi High Council and recognition as one of the greatest Jedi Masters who ever lived. In the last decades of the Republic, he served as Grand Master, the leader of the Jedi Order. He also instructed Younglings in the ways of the Force.
Yoda was one of the first Jedi to sense a disturbance in the Force relating to the Chosen One, a prophesied being who could return balance to the Force.
He eventually found the potential Chosen One in Anakin Skywalker, a 9-year-old human slave found on Tatooine by Qui-Gon Jinn. Yoda recommended against training Anakin, sensing that he had too much anger within him, but Obi-Wan Kenobi trained Anakin to honor Qui-Gon's dying wish. Yoda also sensed that the Jedi Order's perception was clouded by the dark side.
Too late, Yoda learned that the Sith were already controlling the Republic. Chancellor Palpatine, also known as Darth Sidious, turned Anakin to the dark side, ordered the Jedi slaughtered, and declared himself Emperor. Yoda fought him in a duel, but lost.
In this moment, Yoda realized that even with his nearly 900 years of experiences as a Jedi, he still did not know all he should about the Force. He went into hiding on the planet Dagobah, a nearly abandoned swamp where dark side energy disguised his presence. There he studied the Force under Qui-Gon, who had learned to communicate after his death.
Yoda went on to train Luke Skywalker, Anakin's son, believing him to be the last hope for the survival of the Jedi. Yoda died of old age in 4 ABY and became a Force ghost, a technique he learned from Qui-Gon.