The history of Shinjuku dates back to the Edo period, one of the most significant eras in Japan's history. In 1698, a new post station was established on the important Koshu Kaido highway, which connected the capital of Edo (modern-day Tokyo) with the western provinces. It was named "Naito-Shinjuku," which literally translates to "Naito's New Inn"—after the feudal clan that owned the land. This station became a resting place for travelers, merchants, and officials, laying the foundation for the district's future prosperity.
Two key events served as major factors in Shinjuku's emergence as a major center. The first was the opening of the railway station in 1885, which gradually evolved into a bustling transportation hub. However, the real catalyst for development occurred after the Great Kanto Earthquake in 1923. Shinjuku, situated on a geologically stable plateau, suffered significantly less damage than the historic center of Tokyo. This led to a mass migration of residents and businesses from the devastated eastern districts, triggering rapid growth and urbanization.
Originally, Shinjuku was known as a lively destination for leisure and entertainment, drawing large crowds. Its geographic location at the intersection of trade routes fostered a vibrant commercial environment. Following the 1923 earthquake, the first department stores, cinemas, and modern buildings began to appear, transforming the former post station into one of Tokyo's primary commercial and cultural hubs. These historical events shaped the face of modern Shinjuku—a dynamic district of skyscrapers, business activity, and vibrant cultural life.