Legend of the Five Rings: Rise of the Four Winds
Clans of the Empire
The Great Clans were each formed by one of the Kami after their fall from Tengoku, and their histories dated back to the very beginning of the Empire. An exception was the Mantis Clan, which until the Second Day of Thunder was actually a Minor Clan, but through force and manipulation, Yoritomo was able to get his family granted Great Clan status in 1128.
The Great Clans were made up of several family lines, and each Family had their own general purpose within the Clan. Each Clan also had a specific purpose within Rokugan — some area of expertise or mandate that the specific Clan could fulfill better than any others.
There were many minor clans in Rokugan — clans that had been formed since the birth of the Empire by those other than the Kami. New clans were not founded lightly, and the founders of these clans generally performed some extraordinarily valiant deed or favor for the Empire. Unlike the Great Clans, minor clans generally only had one family, but like the Great Clans, each usually had a specific duty they fulfilled.