Study on the early Keyhole-shaped tumulus mounds and their political background in eastern part of Shikoku

本研究的目的是检验和确保研究者的假设，即日本古坟早期存在几个自治的政治单位。每个单位都以自己的主动而不是强制的方式支持基奈政体。为了进行这项研究，研究人员选择了被称为德岛和兵库县当地酋长墓地的锁眼形土丘。研究计划如下：1。对目标区一些3世纪晚期的匙孔丘和圆丘进行平面平面测量，详细记录其大小和形态。绘制保护各自土丘棺木的石室比例图。研究了它们的轴向等类型学特征。对锁眼形土墩的平面图进行了详细的研究，结果倾向于支持研究者的假设。德岛县的前山1号土丘的大小几乎是兵库县的山山1号土丘的一半，山山1号土丘的大小是兵库县的Yorohisagozuka土丘的三分之一。此外，兵库县的京云岛屋土丘的大小是Yorohisagozuka土丘的一半。它们都被认为是最早的锁眼丘类型。这表明目标地区的人们或当地酋长打算根据当地的基本规划建造这四个土丘，每个大小都反映了各自的政治地位。更重要的是，当考虑石室轴线的方向时，在目标区域以“东西型”轴线为主，而在基奈地区以“南北型”轴线为主。这表明目标地区的当地酋长建立了自己的丧葬仪式规则。根据这些事实，可以指出，在目标地区有自治的政治单位，这可能参与了基奈政体的建立。

The aim of this study is to examine and ensure the hypothesis of the researcher that there were several autonomous political units in early Kofun period in Japan. Each unit supported Kinai polity with their own initiative rather than by enforcement from it.To carry out this study, the researcher have chosen the Keyhole-shaped mounds which are known as burial mounds of local chiefs in Tokushima and Hyogo Prefectures.The research plan is as follows:1. To make plane table survey of some Keyhole-shaped mounds and round mounds of the target area, which belongs to late 3rd century with detailed account of their size and form.2. To make scale drawings of some stone compartments protecting coffins of respective mounds. Their typological features such as direction of axis are investigated.The result of detailed research on plans of Keyhole-shaped mounds tends to support the hypothesis of the researcher. Maeyama-1 mound in Tokushima Prefecture is almost one-half the size of Yakuyama-1 mound in Hyogo Prefecture, and Yakuyama-1 mound is one-third the size of Yorohisagozuka mound in Hyogo Prefecture. Furthermore, one-half the size of Yorohisagozuka mound is Keiunjimaya mound in Hyogo Prefecture. All of them are considered to be the earliest type of Keyhole-shaped mounds. This suggests that people or local chiefs in target area intended to build these four mounds accordingly to the local basic plans, each size reflecting their respective political status.Still more, when the direction of the axis of stone compartment is considered, "east-west type" axis dominates in the target area, whereas "north-south type" dominates in Kinai region. This indicates that local chiefs in target area established their own rules for their funeral rites.Based on these facts, it can be pointed out that there were autonomous political units in the target area, and this may have participated in establishing Kinai polity.