In the world of noblemen, a family formation developed based on government positions, court ranks and territorial lands; during the prime of the medieval ages, families were formed among lower-ranking nobles and the ruling class in cities.
つぎに自由貴族においても官職や位階、領地を基盤として家門形成が進み、中世盛期には下級貴族や都市の支配階級においても家門が形成された。