British Military History encompasses the military events, strategies, and conflicts involving Britain from ancient times to the present. Key periods include the Roman conquest, the Hundred Years' War, and the Napoleonic Wars. The British Army and Navy played significant roles in expanding the British Empire, influencing global politics and trade. In the 20th century, Britain faced major conflicts such as World War I and World War II, which shaped modern military tactics and international relations. The Cold War era also saw Britain involved in various conflicts, including the Falklands War, reflecting its ongoing military presence and influence worldwide.