The Junkers ( YUUNG-kər; German: [ˈjʊŋkɐ]) were members of the landed nobility in Prussia. They owned great estates that were maintained and worked by peasants with few rights. These estates often lay in the countryside outside of major cities or towns. They were an important factor in Prussia and, after 1871, in German military, political and diplomatic leadership. The most famous Junker was Chancellor Otto von Bismarck. Bismarck held power in Germany from 1871 to 1890 as Chancellor of the German Empire. He was removed from power by Kaiser Wilhelm II.

Many Junkers lived in the eastern provinces that were annexed by either Poland or the Soviet Union after World War II. Junkers fled or were expelled alongside other German-speaking population by the incoming Polish and Soviet administrations, and their lands were confiscated. In western and southern Germany, the land was often owned by small independent farmers or a mixture of small farmers and estate owners, and this system was often contrasted with the dominance of the large estate owners of the east. Before World War II, the dividing line was often drawn at the river Elbe which was also roughly the western boundary of Slavic settlement by the Wends in the so called Germania Slavica prior to Ostsiedlung. The term for the junker dominated East was thus Ostelbien or East Elbia. They played a big role in repressing the liberal movement in Germany.