Title: Military History of Japan I. Introduction Japan has a long military history and has undergone an evolution from ancient warfare to modern warfare. This article will introduce the development of Japan's military history, including the characteristics and influence of Japan's military in different periods, as well as its impact on the outside world. 2. The Origins of Ancient Military As early as ancient times, Japan's military system began to take shape. During this period, Japan's social structure was mainly based on clans and villages, so its military organization was also regional and familial. At that time, the social environment in Japan was full of wars and conflicts, and the transmission and development of military skills became an important activity among tribes and villages. From the gradual rise of the samurai class, Japan's military system gradually took shape. III. Medieval Military Transformation After entering the Middle Ages, Japan's military system underwent major changes. During this period, the samurai class gradually rose to prominence and developed a unique samurai culture. The military organization also gradually formed a military group with the samurai as the core. In addition, with the advent of the Warring States period in Japan, the scale and form of warfare have changed dramatically, promoting the innovation of Japan's military technology and the development of weapons. During this period, Japan's military power began to develop in the direction of centralization. Fourth, the transformation of modern military affairs After entering modern times, with the invasion of Western powers and the transformation of Japan society, Japan's military system underwent a major transformation. After the Meiji Restoration, Japan began a process of modernization and established a modern army. With the continuous advancement of army building and the introduction of technology, Japan's military strength has gradually grown. At the same time, Japan's foreign expansion and participation in wars of aggression have also had a tremendous impact on Asian countries. During this period, Japan's military strategy and tactics were influenced by the West, and a unique Japanese military system was gradually formed. 5. Modern military development After World War II, Japan's military development underwent significant changes. With the formulation of the pacifist constitution and the pressure of the international community, Japan's military power was severely limited for a time. However, with the changes in the international situation and the changes in Japan's security environment, Japan's military strength has gradually strengthened. Japan's Self-Defense Forces have gradually developed into a modern armed force with advanced technology and strong combat effectiveness. At the same time, Japan has made remarkable progress in military technology, equipment and training. In addition, Japan has demonstrated its important role in international affairs by actively participating in international peacekeeping and humanitarian relief operations. VI. Conclusions In general, Japan's military history has undergone an evolution from ancient times to modern times. In the process, Japan's military system, technology, and culture have undergone tremendous changes. Although Japan's historical foreign expansion and wars of aggression have had a great impact on Asian countries, after World War II, Japan gradually embarked on the path of peaceful development. Today, Japan's military force has developed into a modern armed force with advanced technology and strong combat effectiveness, and plays an important role in international affairs. It is hoped that this article will help readers better understand the development and influence of Japan's military history.