From 2005 to 2012, Japan discussed the possibility of changing the laws of succession to the Chrysanthemum Throne, which is currently limited to males of the Japanese Imperial Family. As of 2021, there are three people in the line of succession to the current Emperor Naruhito: Crown Prince Akishino, Prince Hisahito, and Prince Hitachi. Prior to the birth of Prince Hisahito in 2006, the government of Japan considered changes to the Imperial Household Law to allow additional potential successors to the throne. Background Traditionally, the imperial throne was passed on under custom which resembled the rule of agnatic seniority. Theoretically, any male or female with patrilineal lineage to early Japanese monarchs, who descended in direct male line from the first emperor, Jimmu, could come to hold the throne. In practice, preference was given to first-born male offspring of a preceding male monarch, followed by his brothers, sons, other males of the immediate male-line family, and ultimately male members of the Shinnōke houses, cadet branches distantly related to the reigning monarch. Because there existed no restrictions on remarriage or polygyny in historical Japan, there existed usually many male relatives who could take over the throne. However, there have been several instances of a woman serving as a reigning Empress of Japan. All reigning empresses were descendants of the Imperial Dynasty in the male line. Such successions have happened for a variety of reasons. On some occasions, the direct male heir was only a toddler and unable to perform the imperial rituals. In such an instance, his mother, aunt or elder sister, if also of Imperial lineage through her patriline, temporarily took over the throne until the child came to puberty, which was deemed sufficient for a boy's accession. An empress' offspring also did not have claim to the throne from the said maternal lineage, because all historical reigning empresses were either empresses consort or crown prince spouse before their enthronement, or unmarried through their lives, so assigning a female to the throne had the convenient effect of postponing succession disputes. The last time Japan had a reigning empress was in 1771, when Empress Go-Sakuramachi abdicated in favor of her nephew, Emperor Go-Momozono. After the Meiji Restoration, Japan imported the Prussian model of imperial succession, in which princesses were explicitly excluded from succession. The Japanese government also banned polygyny, which was previously allowed to any family with noble rank (samurai or kuge)