1840 – In a rematch of the 1836 election William Henry Harrison and Martin Van Buren run against each other. This time Harrison wins. Many feel that Van Buren’s term was doomed by the economic depression.
1840 – Official U.S. census shows that the population has reached 17,000,000.
1840 – America’s first dental school is established in Baltimore, Maryland.
1841 – William Henry Harrison dies just 30 days after being inaugurated as president. First chief executive to die in office. Vice President John Tyler is sworn in as president.
1841 – Samuel F.B. Morse patents the telegraph. Instant long distant communication is now possible using a code devised by Morse.
1842 – Webster Ashburton Treaty is negotiated and ratified. It settles the boundary dispute between the U.S. (the area of northern Maine) and Canada.
1843 – Edgar Allen Poe publishes chilling tale of suspense and torture during the Spanish Inquisition, The Pit and the Pendulum. Instantly popular among American readers.
1843 – Elias Howe patents the sewing machine. Revolutionizes the textile industry. Will soon become a household fixture, especially in rural America.
1844 – Nitrous Oxide first used by dentists as anesthesia. Patients claim no pain during procedures.
1844 – Angry mob breaks into the local jail and kills Mormon leader Joseph Smith and his brother in Carthage, Illinois.
1845 – By way of congressional joint resolution, Texas is annexed to the United States. Admitted as the 28th state.
1846 – Dispute of national boundary sparks war between the United States and Mexico. Mexico claims the Nueces River as the true boundary, while the U.S claims the Rio Grande as the boundary.
1846 – Treaty with Great Britain establishes the boundary between the United States and British North America (Canada) at the 49th parallel.
1847 – Under the direction of General Winfield Scott, U.S. forces land at Vera Cruz and move inland to take the capital city of Mexico.
1847 – Under the leadership of Brigham Young, the Mormons settle in the area of the Great Salt Lake.
1848 – United States and Mexico conclude their war with the signing of the Treaty of Guadalupe Hidalgo.
1848 – General Zachary Taylor, who gained fame in the war with Mexico, defeats Lewis Cass in the presidential election. Electoral votes: Taylor 163, Cass 127
1848 – Gold is discovered near a sawmill in California on land owned by John Sutter.
1849 – Thousands and thousands rush to California’s Bay Area to seek their fortunes. Most of the “49ers” fail to find any gold at all. Others find creative way to exploit the situation and make money.
1849 – Harriet Tubman, who will become the best known “conductor” on the Underground Railroad, escapes from slavery.
New States entering the Union in the 1840s:
1845 – Florida, the 27th state
1845 – Texas, the 28th state
1846 – Iowa, the 29th state
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1848 – Wisconsin, the 30th state</p">