Code Geass: Hangyaku no Lelouch

In the year 2010, the Holy Empire of Brittania declared war on Japan. Powerless to stop them, Japan surrendered in less than a month. Freedom was lost and Japan was renamed "Area 11" and its people became known as "Elevens." Lelouch is a Brittanian and his friend Suzaku, born an eleven, has achieved the status of honorary Brittanian. As a boy Lelouch vowed to crush his own government, but now seven years later and in high school, he's accepted that he can't change anything. That is until he meets a mysterious girl that gives him the power to control people's minds - the power of Geass! He dons a mask and becomes the ruthless terrorist known only as Zero, destroying any who might stand in his path - including his boyhood friend Suzaku!

(Source: Bandai Entertainment)