1840 map of us

As of the start of 1840, the Gregorian calendar was 12 days ahead of the Julian calendar, which remained in localized use until 1923. Historical events from year 1840. Learn about 47 famous, scandalous and important events that happened in 1840 or search by date or keyword. 1840 in the United States marked a pivotal juncture, a fulcrum upon which the nation balanced between westward expansion, political realignment, and the escalating moral crisis of slavery. The years from 1840 to 1850 were marked by war, political changes, a gold rush in California, and many other important events in America and around the world. Discover 30 fascinating facts about the year 1840, from historical events to cultural milestones that shaped the world. Dive into history now!

What happened in the year 1840 in history? Famous historical events that shook and changed the world. Discover events in 1840.