Who are the transcendentalists?

The transcendentalists were a group of writers and philosophers in 19th century New England. They believed mainly in the power of the individual, the natural goodness of human nature, the corrupting nature of society and its institutions on the individual soul, and that knowledge comes from intuition and insight, rather than logic and experience. They generally opposed organized religion, industrialization, organized government, and organized social institutions, and instead favored self-reliance, natural living, and ways of living that resembled anarchist, socialist, and communist ideas. Various figures in the movement fought for causes like women's suffrage, better conditions for workers, and changes in religious and educational life in America, generally geared toward respecting the individual power of all men and women and the self reliance of each individual without too much societal influence. Common themes in their writing include nature and its beauty, power, self wisdom, and social change.
Well known transcendentalists include, among others, writer and philosopher Henry David Thoreau, who famously tried to live a self sufficient life at Walden Pond without influence from society; poet Walt Whitman; poet Henry Wadsworth Longfellow; writer, philosopher, and lecturer Ralph Waldo Emerson; writer Nathaniel Hawthorne; critic and teacher Margaret Fuller; teacher Elizabeth Palmer Peabody, who opened the first English language kindergarten in the US; and journalist and reformer George Ripley.
https://www.britannica.com/event/Transcendentalism-American-movement