The eldest son of his father's second marriage, Carlyle always had strong ties to both his parents as well as his eight siblings. His father, a mason and small farmer, wanted Carlyle to become a minister, but Thomas choose to study mathematics instead. He taught math for a while, then, in 1819, returned to Edinburgh University where he unhappily studied law while trying to figure out what to do. He earned money as a tutor, and in 1826 married Jane Welsh, one of his students that he had known for five years.

His first book, "Sartor Resartus" (1833-1834), eventually had great popular success, although initially he had a very difficult time finding a publisher. His next and most important book, "The French Revolution", suffered a serious setback when he sent a partial draft to John Stuart Mill, who accidentally burnt it, wasting months of Carlyle's work. Without money, and with a wife to support, Carlyle worked furiously to finish the book, which was published in 1837 to popular acclaim, solving Carlyle's financial problems. In the 1850s he began a massive study of one of his heroes, Frederick the Great, which was published between 1858 and 1865. His later years as rector of Edinburgh University were not happy; his wife died soon after he became rector, and he spent his final years writing little, generally weary, and living reclusively.