In 1832, Hildreth he became joint founder and editor of a daily newspaper, the
Boston Atlas. In 1834, he wrote a popular anti-slavery novel
The Slave: or Memoir of Archy Moore (1836; enlarged edition, 1852,
The White Slave). In 1837 he wrote for the
Atlas a series of articles vigorously opposing the annexation of Texas. In the same year he published
Banks, Banking, and Paper Currencies, a work which helped to promote the growth of the free banking system in America. In 1838 he resumed his editorial duties on the Atlas, but in 1840 removed, on account of his health, to
British Guiana, where he lived for three years and was editor of two weekly newspapers in succession at
Georgetown. He published in this year (1840) a volume in opposition to slavery,
Despotism in America (2nd ed., 1854). In 1849 he published the first three volumes of his
History of the United States, two more volumes of which were published in 1851 and the sixth and last in 1852. The first three volumes of this history, his most important work, deal with the period 1492–1789, and the second three with the period 1789–1821. The history is notable for its painstaking accuracy and candor, as they are based on very careful analysis of the primary sources. The later volumes favor the
Federalists. In dealing with the Jeffersonians, Hildreth calls them both "Republicans" and "Democrats" on the same page, but never "Democratic Republicans." Hildreth's
Japan as It Was and Is (1855) was at the time a valuable digest of the information contained in other works on that country (new ed., 1906). He also wrote a campaign biography of
William Henry Harrison (1839);
Theory of Morals (1844); and
Theory of Politics (1853), as well as
Lives of Atrocious Judges (1856), compiled from
Lord Campbell's two works. Between 1857 and 1860 Hildreth worked for the
New York Tribune and during the same period he wrote several anti-slavery tracts for the fledgling Republican party under various pseudonyms. Poor health forced him to retire from his writing career in 1860. As a meed Massachusetts Governor
Nathaniel Prentiss Banks and Senator
Charles Sumner successfully lobbied for Hildreth's appointment as the United States
consul at
Trieste in 1861. In 1865 he resigned from that position and moved to
Florence, where he died on July 11, 1865. He is buried near
Theodore Parker in the
English Cemetery, Florence ==Selected works==