Halford Mackinder was a British geographer and politician, best known for his influential theories on geopolitics. Born in 1861, he introduced the concept of the "Heartland," which he described as a central region of Eurasia that holds significant strategic importance. Mackinder argued that whoever controls this area could dominate the world. His ideas were presented in the 1904 paper "The Geographical Pivot of History," where he emphasized the importance of geography in global power dynamics. Mackinder's theories have influenced military strategy and international relations, making him a key figure in the field of geopolitics.