Margaret Bayard Harrison Smith was a prominent member of early Washington City society from the time she and her husband, Samuel Harrison Smith, moved to the blossoming capital in 1800 until her death in 1844. As a longtime resident of Washington, Margaret spent most of her adult life navigating the unique socio-political waters of the capital and developing friendships with many of the most prominent politicians of her time. Mrs. Smith's writings provide firsthand accounts of several important political events including Congress' role in the election of 1800, Jefferson's first inauguration, Madison's first inauguration, and the destruction left by the British after the siege of Washington. Her writings also provide a picture of early undeveloped Washington City, where grand public buildings were largely surrounded by wilderness and connected by muddy roads. While this work looks at the social and political environment that Margaret Smith experienced, it also examines many of the personal concerns that frequented Mrs. Smith's writings. Margaret's views on educating her children, interacting with servants, interacting with the enslaved population of Washington, and dealing with feelings of isolation, due to the distance from her family, are frequently addressed in her letters. Focusing on these aspects of Mrs. Smith's writings allows for a greater examination of the societal norms of her day about gender, class, and race. While Margaret's letters and commonplace books have often been used to examine Washington society and the lives of her prominent friends, there is no biography of Mrs. Smith herself. This dissertation provides the first biography of Margaret Bayard Harrison Smith from her birth until the end of the War of 1812.