Why was ralph ellison considered a prolific author and unique for his time period?

Ralph Ellison, born on March 1, 1914 in Oklahoma City, Oklahoma, studied music before moving to New York City and working as a writer. He published his bestselling, acclaimed first novel Invisible Man in 1952; it would be seen as a seminal work on marginalization from an African-American protagonist's perspective. Ellison's unfinished novel Juneteenth was published posthumously in 1999.

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c. government control over the unsettled western lands