Grand Master

Grand Master was a title given to the oldest and wisest member of the Jedi Order. The Grand Master led the Order's High Council. During the final years of the Order, Yoda fulfilled that function.

Roles and powers
The Grand Master chaired the High Council, a body of twelve Jedi Masters that oversaw and governed the activities of the Jedi Order. The function was fulfilled by the oldest and wisest living Jedi Master. The office of Grand Master was distinct from that of Master of the Order, the holder of which led the Jedi Order as a whole. However, it was possible for a single individual to hold both titles at the same time.

History
During the Clone Wars, the title of Grand Master was held by Yoda. After the Dark Lord of the Sith Darth Sidious managed to kill the majority of Jedi throughout the galaxy, the Grand Master went into hiding on the planet Dagobah. He remained there for over twenty years, until Luke Skywalker came to him for training. Skywalker was trained under the guidance of Grand Master Yoda who ended up becoming one with the Force about a year later.