After the defeat of France in the Napoleonic Wars, the British and Russian Empires expanded greatly, becoming two of the world's leading powers. Russia expanded its territory to the Caucasus and Central Asia. The Ottoman Empire underwent a period of Westernization and reform known as the Tanzimat, vastly increasing its control over core territories in the Middle East. However, it remained in decline and became known as the sick man of Europe, losing territory in the Balkans and North Africa.
Britain, France, Germany, and the United States colonized almost all of Oceania by end of the 19th century. In East Asia, China under the Qing dynasty endured its century of humiliation by foreign powers that lasted until the first half of the 20th century.
Britain's overseas possessions grew rapidly in the first half of the century, especially with the expansion of vast territories in Canada, Australia, India, and in the last two decades of the century in Africa. By the end of the century, the British controlled a fifth of the world's land and one-quarter of the world's population. During the post-Napoleonic era, it enforced what became known as the Pax Britannica, which had ushered in unprecedented globalization on a massive scale.
Jiroemon Kimura (1897–2013) and Nabi Tajima (1900–2018), both Japanese, were the last man and woman respectively verified to have been born during the century.
: United States more than doubles in size when it buys out France's territorial claims in North America via the Louisiana Purchase. This begins the U.S.'s westward expansion to the Pacific, referred to as its Manifest Destiny, which involves annexing and conquering land from Mexico, Britain, and Native Americans.
: The Battle of Trafalgar eliminates the French and Spanish naval fleets and allows for British dominance of the seas, a major factor for the success of the British Empire later in the century.
