A study of political changes in the Kofun period, on specific standards of construction of keyhole-shaped tomb mounds

我们讨论了大型钥匙孔型墓丘的具体建造标准，并提供了它们从库芬期早期到中期的过渡系列。特别是从樱井-长山古方开始的过渡系列，表明大和王朝拥有几个权力。我们对川内地区玉奈山古方群体的土地进行了研究，并对出泉和原马地区的钥匙孔形状的墓丘进行了大地测量。这些研究结果表明，历代国王都会更新自己的墓葬标准，与国王有政治关系的地方酋长也会建造与国王陵墓相似的墓葬。也就是说，科丰标准的过渡系列展示了大和王朝与地方列强之间的政治关系。此外，对类似墓葬的澄清能够指出与国王相对应的具体地方权力。在川内地区，有效的地方权力与钥匙孔形状的陵墓一起交接，同时从Oo-Yamato Koun组过渡到Saki Koun组，再到Furuichi Koun组。同样的情况也发生在出水和原马地区。我们得出的结论是，大和王朝从高芬早期到中期并没有建立起一个政权。我们还估计了两次政治变化，一次是在早期结束，另一次是在古方中期开始。

We discuss specific standards of construction of large keyhole-shaped tomb mounds and provide their transition series from the early to the middle of Kofun period. Especially the transition series started with Sakurai-Chausuyama Kofun indicate that Yamato dynasty had several powers.We conduct research on the land of the Tamateyama kofun group in the Kawachi area, and geodetic surveying of keyhole-shaped tomb mounds in the Izumi and Harima area. Databases of keyhole-shaped tomb mounds across the country are made up and their digitalization is also developed.Results obtained from these researches show that a successive king updates the standard of his own tomb and local chiefs politically related with the king construct similar tombs with the king's tomb. That is, transition series of Kofun standards demonstrate political relations between Yamato dynasty and local powers. Moreover, clarification of similar tombs is able to point out the specific local power corresponding to the king. In the Kawachi area, effective local powers with keyhole-shaped tombs change over in conjunction with transition from the Oo-yamato Kofun group to the Saki Kofun group, and to the Furuichi Kofun group. The same holds in the Izumi and the Harima area. We conclude that Yamato dynasty does not establish one political power from the early to the middle of Kofun period. Also we estimate that two political changes are occurred, one in the end of the early and the other in the beginning of the middle of Kofun period.