In the late-nineteenth and early-twentieth centuries, Japan became much more Westernized, making use of Western methods to develop its economy and modernize its system of government. The abolition of feudalism and the centralization of power facilitated the rise of Japan as a military power, although it wouldn't be until the 1930s, with the invasion of Manchuria, that Japan would prove itself to be a major imperial power.

Nevertheless, in the decades leading up to the invasion of Manchuria, Japan used the science and technology it had imported from the West to industrialize its economy, thus providing the necessary resources for a major expansion of the armed forces.

It wasn't very long before the Japanese were able to test their newfound military strength. Their comprehensive victory over Tsarist Russia in the Russo-Japanese War of 1904 was a clear sign demonstration of strength. It also consolidated the growing political power of the Japanese military—who took full advantage of Japan's centralized, authoritarian system of government to dominate and control civilian politicians.

All of these factors—the centralization of government, the industrialization of the economy, and the widespread use of Western science and technology—combined to lay the foundations of Japan's imperialist aggression during the 1930s and on into the Second World War.