The Japanese government found the concept ideologically problematic, preferring not to have Divine political legitimacy that was conditional and that could be withdrawn. The Japanese Taihō Code, formulated in 703, was largely an adaptation of the governmental system of China's then Tang dynasty, but the Mandate of Heaven was specifically omitted. In later times, this need was obviated because the Imperial House of Japan claimed to be descended in an unbroken line from the Japanese sun goddess, Amaterasu. Nevertheless, while maintaining this role, the Japanese Emperor became politically marginalized in the Nara and Heian periods by powerful regents of the Fujiwara clan who seized executive control of state. Even though the Japanese imperial line itself remained unbroken after the eighth century, actual political authority passed through successive dynasties of regents and shōguns which cycled in a manner similar to that of Chinese dynasties. Even after the Meiji Restoration in 1868, when the Emperor was placed back in the center of the political bureaucracy, the throne itself had very little power vis-à-vis the Meiji oligarchy. Actual political power has passed through at least four systems since the Meiji restoration: the Taishō democracy, the militarists, the Occupation of Japan, and postwar democracy. The Emperor today is a political figurehead and not a ruling sovereign. It could be said the imperial line of Japan survived for so long precisely because it did not have control over the state, and that the turmoil of succession was projected onto a series of proxy rulers.