Chancellor Palpatine heads the Senate of the Galatic Republic, having wormed his way into the position using his brilliant political skills.
Originally a senator from the planet Naboo, Palpatine was appointed the head of the Senate after the man before him was kicked out - something Palpatine may have had a hand in.
10 years after taking charge a threat to the Republic from separatists forces saw the Senate take action to try and stop.
They gave Palpatine power to make new laws without needing approval from the other senators, and he started by building an army to fight for the Republic.
When the threat from the separatists is removed Palpatine has promised to return his power to the Senate, but if the battle continues who knows how long he will be in charge...