The Prussian Monarchy was a significant political system in Europe, primarily from the 16th century until the early 20th century. It was centered in the region of Prussia, which is now part of modern-day Germany. The monarchy played a crucial role in the unification of Germany and was known for its strong military tradition and efficient bureaucracy. The most notable monarchs included Frederick the Great, who expanded Prussia's territory and influence in the 18th century, and Wilhelm I, who became the first Emperor of a unified Germany in 1871. The monarchy ended with the abdication of Kaiser Wilhelm II in 1918, following Germany's defeat in World War I.