BontenMaru takes its name from a legendary historical figure, Date Masamune (1567-1636), the founder and the first daimyou of Sendai. Inspired by a dream his mother saw when she was pregnant with him, he was called "Bontenmaru". "Bonten" is a Buddhist ritual scepter. "Maru," literally meaning "round" or "circle," is a common term of endearment for a young boy.

Bontenmaru was brought up as a prince at Yonezawa Castle in present-day Yamagata prefecture. He lost the sight of his right eye from smallpox when he was a young child and later came to be referred to as the "Dokuganryu" or One-eyed Dragon. During the chaos of the civil war in the late 16th century, Bontenmaru, now known as Date Masamune, attempted to unite the northern provinces. Encouraged by some initial successes, he even dreamed of ruling all Japan. But this was a vain hope, as his rivals, Toyotomi Hideyoshi and Tokugawa Ieyasu, managed to unite the country under their rule. Masamune moved northward in 1600 and became the first daimyou of what is now Sendai. He is known for his efforts to establish cultural links with Europe. For example, in 1613 he sent an envoy to Rome in one of the first Japanese missions to the West. 

Naming the robot "BontenMaru" not only makes it a more entertaining educational tool for children, but also helps to interest them in the past by blending history and romance with science and technology. Enlivened by its historical associations, BontenMaru goes forth from Sendai to inspire the children of the world.