In Japan from ancient time chronology was not based on an era. Originally the method pursued was to reckon years after the accession of each emperor to the throne. In 645 A. D., however, was introduced the Chinese fashion of using year periods designated usually in two felicitous Chinese characters and changed as frequently as was desired. The change of the name of a year period thus occurred at the beginning of each new reign, and also on the recurrence of a cyclical year of ill-omened designation, as well as on occasions of exceptional good or bad fortune, so that there are extreme instances of five or six changes of designation within the reign of one single emperor. It results, of course, that a troublesome effort is required to commit to memory the sequence and dates of the various year periods. The Chinese, in the reign of the Ming sovereign Taitsu, decided that there should be no change in the designation of a year period throughout the reign of a sovereign. A similar ruling was made in 1868 on the accession of the present Emperor of Japan, from which time also the era of Jimmu began to be used as a chronological basis. This latter era is officially fixed at 660 B. C.[1] As to the later sources of Japanese history, following the already mentioned "_Kojiki_" and "_Nihongi_," they are abundant, increasing as we move further from earlier ages. Much of this vast historical literature has been published and edited (though thus far little translated into European languages), but more has neither been extensively circulated nor even seen light. The Japanese Government, which has been searching for hidden material all over the land, is now publishing, through the Imperial University of Tokyo, historical documents, mostly unpublished hitherto, in two large series[2] of two and three hundred volumes, respectively, to be completed in about fifteen years. The history of Japan does not lend itself to the customary division of the ancient, mediæval, and modern ages. On the basis of the important changes that have taken place in the administration and politics of Japan, her history will, in the following pages, be divided into three parts of unequal lengths. Part one covers the long space of time between the founding of the empire and the beginning of the feudal régime toward the end of the twelfth century. During this period, the power of the government rested, theoretically, in spite of great fluctuations which took place, in the hands of the sovereign. This was followed by nearly seven centuries of military autocracy, which constitutes the second part. The third part begins in 1868, since which year administrative power has reverted to the emperor, a constitutional régime with representative institutions has been established, and the general aspects of the life of the nation have undergone a profound change. FOOTNOTES: