Definitions

Daimyo - Warlords, land owners, controllers of samurai. In Japan's social hierarchy, daimyo were under the shogun.

Samurai - Originally defined as "one who serves," samurai were warriors in Japan. Their role changed greatly throughout the different eras of Japanese history. In most eras, they are higher ranked officers, not the whole army. Their daimyo is their master. Similar to knights in European history.

Shogun - The military leader of Japan, and during the shogunate, the person at the top of the Japanese social hierarchy. The shogun was not the emperor, and while he was technically below the emperor, the emperor only really had religious and symbolic power, while the shogun was really in charge of Japan.

Shogunate - The years that the shogun was in power in Japan, while the beginning year of the shogunate is debatable, the shogunate lasted roughly from the late twelfth century CE to the nineteenth century CE.

Seppuku (Suicide warning) - Also known as hara-kiri. Ritual suicide, very common among samurai. It was thought to be an honorable way to die, as samurai, and many Japanese people of the time, would have rather killed themselves than die to an enemy, or be dishonored in another way. It was incredibly painful. Samurai would cut across their abdomens, disemboweling themselves. It was common to have a second person behind the samurai, with a sword ready to behead them a few seconds after they had made the cut. Those who did not have a second died slowly and painfully.