Answer:
1. In the past, since it was an island, it was hard for invaders to come unless they had good ships. For example, the Mongols who tried to conquer Japan were defeated by a natural disaster, the typhoons, before they got there. But because it was hard for foreign people to come, they didn't develop as fast as the Western world. Their "industrialisation period" happened a lot later. Japan was influenced most by China, but still was mostly isolated most of the time with no foreign threats so they had homogeneity and the country developed at its own pace creating a unique culture etc.
2. After the Meiji Restoration, someone there had the idea to conquer the world (basically fight other nations to gain land). Because they are an island, they can't have foot-military right? Thus they developed very strong maritime technology and strong marine troops that actually were able to conquer a bunch of places like Korea or the Phillippines.
3. Terrain also influences where the major cities/ towns are. Japan has volcanoes and mountains and all of that PLUS it has a lot of natural disasters. They had to find the best places to build civilisation. Also, the Japanese had to develop ways to survive like building structures that could withstand earthquakes or to hide from volcanic explosions or tsunamis. Not only the physical things, it has also made the residents of Japan very alert and aware of natural disaster situations, and know how to handle themselves in it.