Born into an aristocratic South Carolina family, Louisa McCord attended girls' schools in Philadelphia and learned mathematics and Latin with her brothers. Struggling, against her own ambition, to adapt to her father's and the era's standards of femininity, she took over the family's Lang Syne cotton plantation in Columbia, South Carolina, and married politician David James McCord. They had three children, and Louisa McCord carefully educated and groomed her only son for a career in politics.
In 1848 her husband asked her to translate Bastiat's Sophimes Économiques, an essay which argued against protective tariffs, and her skilled translation attracted the attention of editors who solicited her essays on economics, politics, slavery, and women's rights. Most of these essays appeared anonymously or with only her initials, for Louisa McCord's contemporaries would have considered it highly indelicate for a woman to publish on such controversial issues. In her work, she defended slavery and argued that women should have access to education but refrain from public life, writing that "woman was made for duty, not for fame."
Her husband died in 1855, and during the Civil War she assumed presidency of both the Soldier's Relief Association and the Ladies' Clothing Association and worked for the military hospital at South Carolina College. After her son died in the Battle of Bull Run and the war ended in southern defeat, she bitterly fled to Ontario rather than take the required oath of allegiance to the federal government. Eventually she returned to the United States and spent the rest of her life with her daughter in Charleston.