1840

1840 was a leap year in the Gregorian calendar, marked by notable political and social developments across the world. Several long-standing processes of modernization and colonial expansion continued to shape politics, economy, and culture.

In the United Kingdom, postal reform took a decisive step with the introduction of the Uniform Penny Post and the first adhesive postage stamp, the Penny Black, introduced in 1840, making mail more affordable and standardizing rates.

In North America, the Act of Union 1840 united Upper and Lower Canada into the Province of Canada, effective in 1841, creating a single legislature for the merged colonies.

Treaty and colonial relations: On February 6, 1840, the Treaty of Waitangi was signed in New Zealand between the British Crown and many Māori chiefs, establishing British sovereignty and a framework for governance that would shape New Zealand’s political development.

Conflicts and imperial diplomacy: The First Opium War between Britain and Qing China continued, underscoring tensions in East Asia over trade and narcotics, and culminating in the 1842 Treaty of Nanking.

In the United States, the 1840 presidential election brought Whig William Henry Harrison to the presidency, defeating incumbent Martin Van Buren; the campaign popularized frontiersman imagery, and Harrison’s presidency was short-lived, ending with his death in 1841 and succession by John Tyler. The 1840 census recorded roughly 17 million residents.