A leading transcendentalist during the period of westward expansion was

Ralph Waldo Emerson was a leading transcendentalist, promoting individual intuition, self-reliance, and a close connection with nature. Emily Dickinson and Nathaniel Hawthorne were important writers but were not leading figures in the movement; John L. O’Sullivan is known for popularizing the idea of Manifest Destiny. The correct choice is Ralph Waldo Emerson.

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