The following summary comes from Wikipedia (but it's pretty accurate from what I've seen so far):
On August 10th, 2010, a.t.b., the Holy Empire of Britannia overpowered Japanese forces and conquered the country with their robotic weapons, the Knightmare Frames, in less than a month. Japan lost its freedom and rights and was renamed Area 11. The Japanese people, renamed as "Elevens", were forced to survive in ghettos, while Britannians lived in first-class settlements. Rebel elements persisted, however, as pockets of Japanese organizations who struggled against the Empire for the independence of Japan.
After his father, the Emperor of Britannia, did nothing to pursue the terrorists who murdered his mother and crippled his sister, the young prince named Lelouch vowed to destroy Britannia. Seven years later, living in Area 11, he encounters a mysterious girl who gives him the power of Geass. With it, he finally has the power that he needs to defeat Britannia and fulfill his two wishes: to seek revenge for his mother and to construct a world in which his beloved sister can live happily.
The show brought up plenty in my head from past classes and the shows regard to Britain as an oppressive power that conquers and leaves to rot reminded me of the documentaries we watched about Ireland and India suffering under the hard oppressiveness of Britain during it's imperialistic phase. The fact that Japan and it's people get a name change to Area 11 and Eleven's respectively was a real shock as to how far Britannia would go to instill its order upon the weakened and oppressed people.
History lessons aside, from what I've seen of this show so far, it is a lot of fun to watch. But, f course, some people need that particular studious reason to watch any particular program, so that's my reason for most of you. For me, Code Geass not only let me apply what I've learned in class to my favorite medium (I can't believe I just typed that), but gave me a reason to love Anime all over again.
Ladies and Gents, Code Geass can be found anywhere online, but if you want an English dubbed version, it will premiere at the end of April on Cartoon Network's Adult Swim Saturday Action Block. Check it out.