The following articles contain information on the families that comprise the Imperial Families.
“The Yotsu family were a ronin family who were given their name and duty by the Emperor Hantei...Yotsu family
“The Hantei family were founded by Hantei at the Dawn of the Empire and would become the Emperors...Hantei family
“The Iweko family was formed after Kitsuki Iweko became Empress of Rokugan. The line would be...Iweko family
“The Toturi family was one of Rokugan's Imperial Families and was formed after Toturi became...Toturi family