shogun vs. emperor

shogun

[shoh-guhn, -guhn] / ˈʃoʊ gən, -gʌn /

Or shōgun

noun

Japanese History.

the title applied to the chief military commanders from about the 8th century a.d. to the end of the 12th century, then applied to the hereditary officials who governed Japan, with the emperor as nominal ruler, until 1868, when the shogunate was terminated and the ruling power was returned to the emperor.

emperor

[em-per-er] / ˈɛm pər ər /

the male sovereign or supreme ruler of an empire.

the emperors of Rome.
Chiefly British. a size of drawing or writing paper, 48 × 72 inches (122 × 183 centimeters).