Important and uncommon map - Ephraim Gilman’s 1848 Map of the United States, Now Expanded Coast to Coast. The map reflects President Polk's view that the best solution to the sectional crisis over slavery in the territories was the extension of the Missouri Compromise line to the Pacific Coast. The marking of the proposed California state boundary on the Archives copy of the map used during the course of the debate over the Compromise of 1850 makes it a unique document. Framed under glass in gilt wood frame. In frame measures 37"x17 1/4"x1". Weight 5 pds 6 oz. PROVENANCE: A Private Charleston SC Estate. In December 1848, the U.S. General Land Office produced a map of the United States by its principal draftsman, Ephraim Gilman. It displayed all the existing states, territories, proposed territories, and the area of the Mexican Cession in the southwest acquired by the terms of the Treaty of Guadalupe Hidalgo, which ended the war with Mexico. The Gilman map was specifically ordered by President James K. Polk to accompany his last annual message to Congress that month. Polk wanted the map to illustrate the territorial gains from the Mexican War, advance his ideas on the development of the newly acquired territories, and address the growing debate in Congress and the nation over the extension of slavery in the territories. Gilman colored the various areas in pink, light green, and light yellow and featured tables of statistics on the square miles and acreages on the right and left borders. The map is a beautiful artifact on its own, but it is also an intriguing document with features that are not immediately obvious. While the Gilman map appears to be a credible rendering of the United States at mid—19th century, closer inspection reveals serious labeling errors, misspellings, and egregious misplacements of major geographic features. This is surprising because Gilman was an experienced draftsman who had been at the land office at least since 1839. The Gilman map shows that the 1840s had been an important decade for the expansion of the United States. The Texas annexation by the United States in 1845 brought Texas into the Union as a slave state. In 1846, the British ceded the Oregon Territory south of the 49th parallel: what is now Washington, Oregon, Idaho, and part of and Montana. In the 1848 Treaty of Guadalupe Hidalgo after the Mexican War, Mexico ceded what are now the states of California, Nevada, and Utah and parts of Colorado, Wyoming, Arizona, and New Mexico. The United States now reached coast to coast, a fact that the expansionist President Polk wanted to highlight in this unique but forceful political statement.