These relationships based on the blood family community with primogeniture at its core is called the Sozoku System, and it is generally accepted that the Sozoku system and Hoken system were closely related to each other.
長子相続を根幹とした血族共同体を基礎としたこの関係を宗族制度といい、宗族制度と封建制度が密接に関係していたであろうことは概ね認められている。