250 Years of Isolation, Then the Black Ships — Why Japan Was Never Colonized

Standing at the Port of Yokohama

Look out at the sea from Yamashita Park in Yokohama. You'll see a massive cruise ship terminal, the high-rise skyline of Minato Mirai, and factory smokestacks in the distance. The most international port city in Japan.

But 170 years ago, there was nothing here. Yokohama was a tiny fishing-and-farming village of maybe 100 households.

On July 8, 1853, four warships led by U.S. Navy Commodore Matthew Perry appeared off the coast of Uraga, about 30 km south of Yokohama. The Japanese called the steam-powered vessels with their black hulls kurofune — Black Ships.

Those four warships pried open a door that had been shut for 250 years. Just 15 years later, in 1868, Japan had completely overhauled its political system — from the Edo Shogunate to the Meiji government — and became one of the fastest-modernizing nations in Asia.

Why did Japan close itself off? Why was it forced to reopen? And why, while so many countries across Asia and Africa were being colonized, did Japan manage to stay independent?

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Why Japan Closed Its Doors

The Shogunate's Reasons for Shutting Out the World

Japan's isolation policy, known as sakoku, was established in stages by the Tokugawa Shogunate during the 1630s. The motivations were multiple.

The Christian threat. In the late 16th century, Portuguese and Spanish missionaries arrived in Japan and spread Christianity. At its peak, the number of Japanese Christians (Kirishitan) is believed to have reached several hundred thousand. The Shogunate saw this as a threat — not for religious reasons, but for political ones. The Christian idea that all people are equal before God clashed head-on with the rigid four-tier class system of warrior, farmer, artisan, and merchant. For believers, the highest authority was God, not the Shogun. Some Christian feudal lords (daimyo) had deep ties to European religious powers — Omura Sumitada, for example, donated the port of Nagasaki to the Jesuits.

Trade monopoly. During the Warring States period, feudal lords in western Japan had been getting rich through trade with Portugal and Spain — the so-called Nanban trade. For the Shogunate, the prospect of rival lords amassing wealth and weapons through independent trade was an existential risk to the whole feudal order. By funneling all trade through Nagasaki under Shogunate control, that economic threat was neutralized.