In what time period did Western powers forcibly open Japan to foreigners?

The mid-19th century is the correct time period when Western powers forcibly opened Japan to foreigners. This significant event is commonly associated with Commodore Matthew Perry's expedition in 1853, which resulted in the signing of the Treaty of Kanagawa in 1854. This treaty marked Japan's first official agreement with a Western nation and effectively ended over two centuries of Japan's self-imposed isolation under the Tokugawa shogunate, which had maintained a policy of sakoku—restricting foreign contact and trade.

The mid-19th century was characterized by global expansion and imperial pursuits by Western powers, particularly in Asia. Japan's opening to foreign trade led to several treaties with other nations, subsequently transforming Japanese society, economy, and its role in international relations. This era set the foundation for Japan’s modernization and industrialization, making it a significant period in both Japanese and world history.