Final answer:
Emily Dickinson is the American poet known for her extensive correspondence with her brother's wife and her highly regarded poetry, which explored themes like the natural world and the soul's independence, later recognized for their modernist qualities.
Step-by-step explanation:
The Famous American Poet
The famous American poet who engaged in extensive correspondence with her sister-in-law and also wrote many poems is Emily Dickinson. While Dickinson is often incorrectly depicted as reclusive and timid, her poetry reveals a technically skilled and innovative writer, whose themes often explored the individual will and the natural world, as seen in her lyrical masterpieces like “I taste a liquor never brewed -” and “The Soul selects her own Society -.” Her writing style and intense private correspondence characterized her relationships, particularly the notable one with her brother's wife, Susan Gilbert Dickinson. Unlike Sylvia Plath, Emily Dickinson's technical prowess and thematic concerns with nature and the soul's independence were well ahead of her time, displaying a modernist quality that would point towards the future direction of American poetry.
Despite the family connections, community ties, and public socialization, Dickinson often lived a life of seclusion, which was her personal choice. Her work was revolutionary in its disregard for conventional meter, use of slant rhyme, and its thematic exploration of topics like love, nature, and immortality. Most of Dickinson's correspondences and poems were discovered posthumously in a drawer, leading to her eventual recognition as a significant American poet.