Pax Britannica (Latin for 'British Peace', modelled after Pax Romana) refers to the relative peace between the great powers in the time period roughly bounded by the Napoleonic Wars and the First World War. During this time the British Empire became the world hegemon, developed an additional informal empire, and adopted the role of a "global policeman".
Between 1815 and 1914, a period sometimes referred to as Britain's "imperial century", around 26,000,000 square kilometres (10,000,000 sq mi) of territory and roughly 400 million people were added to the British Empire. Victory over Napoleonic France left the United Kingdom of Great Britain and Ireland without any serious international rival, other than perhaps the Russian Empire in Central Asia during the Great Game. When Russia attempted to expand its influence in the Balkans, the British and the Second French Empire defeated it in the Crimean War (1853–1856), thereby protecting the weak and declining Ottoman Empire.
