From an Atlas Obscura posting about the MOST and LEAST agreeable States:
Agreeableness: Social Harmony vs. Self-Interest
People who are “agreeable” aim for social harmony, by being kind and considerate, and are prepared to compromise on their goals. “Disagreeable” people have a less optimistic and less cooperative view of others, giving precedence to self-interest. They are more competitive and argumentative.
The presence of agreeableness is most pronounced in the South (Louisiana to North Carolina, with hotter and colder zones in Arkansas, Kentucky, Tennessee, and Florida). A second important cluster was found in and around Minnesota and the Dakotas. The dark green of disagreeableness hangs heaviest over Western states, from Montana to New Mexico, and from Nevada to the western halves of Kansas and Oklahoma. There is an additional grumpiness epicenter in New England.