Its a PDF compliation of a Open Source Historical encyclopedia for the complete history of Japan, including all ... well hell, its a book in PDF format...
Here is the ToC...
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Table of Contents
Frontmatter........................................................... ......................................5
Abe Family (Mikawa) – Azukizaka, Battle of (1564)..................................11
Baba Family – Buzen Province............................................... ..................37
Chang Tso-lin – Currency............................................... ..........................45
Daido Masashige – Dutch Learning..................................... .....................75
Echigo Province – Etō Shinpei................................................................ ..78
Feminism – Fuwa Mitsuharu................................................... ..................83
Gamō Hideyuki – Gyoki................................................. ...........................88
Habu Yoshiharu – Hyūga Province............................................... ............99
Ibaraki Castle – Izu Province..................................................................118
Japan Communist Party – Jurakutei Castle............................................135
Kaei – Kyūshū Campaign........................................ ...............................139
Lansing, Robert – Lytton.......................................................... ...............178
MacArthur, Douglas – Mutsu Province................................................... .178
Nabeyama Sadachika – Nunobeyama, Battle of.....................................205
Ōan – Ozu Yasujiro............................................. ....................................222
Pacific War – Privy Council.................................................... .................236
(Q: No Entries).................................................................... ....................238
Rangaku – Ryūkyū Province........................................................ ...........238
Sado Province – Suzuki Zenkō.................................................. .............242
Tachibana Muneshige – Twenty-One Demands.....................................271
Uchida Ryohei – Uzen Province.............................................................298
(V: No entries)................................................................................. ........302
Wado Province – Witte, Sergei...............................................................302
(X: No entries)................................................................................. ........305
Yamagata Aritomo – Yūryaku-tennō.................................................. .....305
Zaibatsu – Zeami.................................................... ................................311
Chronological List of Emperors............................................ ...................313
Prime Ministers, 1885 to Present........................................ ....................317
Alphabetical List of the Prefectures........................................................ .320
Provinces and Corresponding Prefectures...................................... ........322
Chronological List of Nengō.......................................................... ..........325
List of the Shōgun....................................................................... ............333
GNU Free Documentation License.........................................................335
I shouldn't say complete... I found nothing about Atsu-Hime in there...