On August 10, 2010, a.t.b. (the Imperial calendar), the Holy Empire of Britannia overpowered Japanese forces and conquered the country with their new robotic weapons, the Knightmare Frames, in less than a month. In the aftermath of Britannia's invasion, Japan lost its freedom, its rights, and even its name, becoming Area 11 of the Britannian Empire. The Japanese people, renamed as "Elevens", are forced to survive in poor neighborhoods, while Britannians live in first-class settlements. Rebel elements persist, however, as pockets of Japanese organizations struggle against the Empire for the independence of Japan.

After his father, the Emperor of Britannia, failed to prevent the assassination of his mother, an attack which also left his sister blind and crippled, the young prince Lelouch vowed to destroy Britannia. Seven years later, living in Area 11, he encounters a mysterious girl named C.C., 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 Holy Empire of Britannia  is an imperial monarchy and the most prominent superpower within the world of Code Geass, controlling over one-third of the world. Its homeland is based in North America, and its imperial city is Pendragon. Britannian society is elitist and closely resembles Social Darwinism. Society is arranged by ranks of nobility.

With the exception of the European countries and parts of North Africa (which it is attempting to conquer), the Britannian Empire controls the entire Western Hemisphere, Japan, New Zealand, parts of the Middle East, and a portion of the Indochina Peninsula in the novels (the maps in later episodes contradict this). Ironically, it does not control the British Isles, as Napoleon managed to successfully conquer the region.

In the series, history diverged during Julius Caesar's invasion. A Celtic "super-king" was elected and managed to successfully resist the invasion, beginning the Britannian imperial line. As a result, the empire retained absolute monarchy, suppressed the American colonies' rebellion in 1776, and eventually migrated the capital to America following Napoleon's capture of Britain.

His Imperial Highness Lelouch vi Britannia

Oh dear, I just watched the trailer... *sigh* animes...

I don't know, animes and I have 'love hate' relationships. It looked like the dubbing was abit cheesy on the first one. I will watch the second later and give an opinion. But in the end, I need to watch a few episodes of the show to give an accurate assessment.

Ouch

Weren't there monarchist themes in Mobile Suit: Gundam Wing?