Suzaku is a prime example of an Honorary Britannian.
An Honorary Britannian is a citizen of the Holy Empire of Britannia who is not of ethnic Britannian descent, and so has vowed loyalty to the Empire to gain citizenship. All non-Britannians living in Britannia-conquered areas are allowed to accept honorary Britannian citizenship. Honorary Britannians are legally almost identical to Ethnic Britannians, but are not free from discrimination. Those living in an Area who do not accept Honorary citizenship are barred from living in the wealthy Britannian colonial cities, and so are often consigned to live in a ghetto.
Honorary Britannians are sometimes employed by the Britannian Army as separate divisions, and usually employed for menial warfare such as hunting down rebels in less favorable conditions, sometimes thet are viewed by their commanding officers as a disposable unit. The Blood-Purist Faction seeks to eliminate all non-Britannians from within the military. Suzaku Kururugi is the first and only Honorary Britannian to become a knight and the only non-Britannian in the Knights of the Round.
Following Lelouch's ascension to the throne, one of his changes to Britannian rule is to liberate previous areas, returning them to their respective government.