As a result of his association with Martin Van Buren, Marcy was appointed comptroller of New York (1823-29), serving admirably in that capacity by forcing fiscal restraint upon the legislature during a time of wild public enthusiasm for funding every canal and railroad venture that was proposed. He went on to serve as U.S. Senator (1831-32), New York Governor (1833-38) and U.S. Secretary of War (1845-49) during the Mexican War. His greatest contribution, however, was as Pierce's Secretary of State (1853-57). During his tenure, 24 treaties were negotiated, the largest number within single administration up to that time. Those of particular importance were the Gadsden Treaty with Mexico (1853) and The Reciprocity Treaty with Britain (1854). Numerous important but delicate cases involving international relations were also settled. Marcy's most serious misstep involved his choice of the individuals who prepared the Ostend Manifesto, a document relating to the manner in which the U.S. might acquire Cuba from Spain. The Manifesto caused a furor at the time of its publication (1855), and temporarily disrupted the U.S.' relations with Spain. At the time of Marcy's death, he was considered to be one of the nation's foremost citizens and, even today, ranks as one of the ablest Secretaries of State.