In Song society, governed by the largely unaltered Tang era legal code, the act of primogeniture was not practiced in Chinese inheritance of property, and in fact was illegal. When the head of a family died, his offspring equally divided the property. This law was implemented in the Tang dynasty in order to challenge the powerful aristocratic clans of the northwest, and to prevent the rise of a society domineered by landed nobility. If an official family did not produce another official within a few generations, the future prospects of that family remaining wealthy and influential became uncertain. Thus, the legal issues of familial inheritance had profound effects upon the rest of society.