Chōshū Domain

The Chōshū Domain (長州藩, Chōshū han^?) was a feudal domain of Japan during the Edo period (1603–1867). It occupied the whole of modern-day Yamaguchi Prefecture. The capital city was Hagi. The name Chōshū was shorthand for Nagato Province. The domain played a major role in the Late Tokugawa shogunate. It is also known as the Hagi Domain (萩藩, Hagi han^?).

The rulers of Chōshū were the descendants of the great Sengoku warlord Mōri Motonari. Motonari was able to extend his power over all of the Chūgoku region of Japan and occupied a territory worth 1,200,000 koku. After he died, his grandson and heir Mōri Terumoto became daimyo and implemented a strategy of alliance with Toyotomi Hideyoshi. This would later prove to be a great mistake. After Hideyoshi's death, the daimyo Tokugawa Ieyasu challenged the Toyotomi power and battled with Hideyoshi's trusted advisor Ishida Mitsunari at the Battle of Sekigahara. Mōri Terumoto was the most powerful ally of the Toyotomi and was elected by a council of Toyotomi loyalists to be the titulary head of the Toyotomi force. However the Toyotomi forces lost the battle due to several factors tied to Mōri Terumoto:

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