Final answer:
The samurai were the warrior elite in Japanese society and served to protect the daimyo, who were powerful feudal lords during Japan's feudal history.
Step-by-step explanation:
The Japanese social role or group that protected the daimyo were the samurai. Samurai were members of the warrior elite and served as loyal retainers to the daimyo. They adhered to a strict code of behavior known as bushido, or "the way of the warrior," and were fundamental in maintaining the power and authority of their daimyo lords throughout Japan's feudal history. The samurai class was below the shogun, who was the military commander and actual ruler of Japan, and above the peasants, craftsmen, and merchants within the country's highly structured societal hierarchy.