Why were the Shintos important to the Early Japanese?

The Shintos were important to the Early Japanese becuase they became the official state religion of Japan

Explanation:

Many shrines were supported by state funding. ... Shinto became the glue that bound the Japanese people together with a powerful mix of devotion to kami, ancestor-worship, and group loyalty to family and nation.

Social isolation of rhesus monkeys for the first 6 to 12 months of life produces severe and persistent behavioral effects including social withdrawal, rocking, huddling, self-clasping, stereotyped behaviors, and inappropriate heterosexual and maternal behaviors as adults.