Supreme Chancellor
Supreme Chancellor (usually just Chancellor) is the title of the Head of State and Government in the Galactic Republic of the fictional Star Wars universe.
The Chancellor is elected by and from the members of the Galactic Senate and serves as long as he or she can maintain the confidence of the house. The Chancellor can be deposed by a vote of no confidence at any time. The Chancellor also serves as the head of the Senate, and the Jedi Council is also nominally under the Chancellor's authority.
The office was largely powerless in the last years of the Republic, similar in nature to a Speaker of the House. The Chancellorship however was still a very prestigious position. despite the loss of power, and Chancellors retained a grand office and the title of "Excellency."
Chancellor Finis Valorum was seen in Star Wars Episode I: The Phantom Menace and presided over the dispute between Naboo and the Trade Federation. He was ousted when Queen Amidala, on Senator Palpatine's urging, moved for a vote of no-confidence.
The office became much more powerful during the reign of Chancellor Palpatine, who was able to effectively force the Senate into granting him a series of "emergency" powers, incluidng creation of the Army of the Republic, making him Supreme Commander-in-Chief of that army, and direct control of the Jedi Order in addition to the Chancellor's existing constitutional control over the Jedi Council. Eventually, Palpatine became a dictator and proclaimed himself Emperor, thus abolishing the office of Chancellor and ending the Republic. This brought about the establishment of the Galactic Empire. The title was not revived by the New Republic/Galactic Federation of Free Alliances, which instead used the term Chief of State to designate the head of government.