Prussia (German Preussen), former kingdom and state of Germany. At the height of its
expansion, in the late 19th century, Prussia extended along the coasts of the Baltic and
North seas, from Belgium, the Netherlands, France, and Luxembourg on the west to the
Russian Empire on the east, to Austria-Hungary on the east, southeast, and south, and to
Switzerland on the south.

Modern Prussia was successively, with geographical modifications, an independent
kingdom (1701-1871); the largest constituent kingdom of the German Empire (1871-
1918); a constituent state, or land, of the Weimar Republic (1919-1933); and an
administrative division, comprising 13 provinces, of the centralized German Third Reich
(1934-1945). After World War I (1914-1918), West Prussia was lost to Poland, and East
Prussia was separated from the rest of German Prussia in 1919, under the terms of the
Treaty of Versailles, by a strip of formerly Prussian territory known as the Polish
Corridor, designed to give Poland an outlet on the Baltic Sea. The other provinces of
Prussia between the two World Wars were Rhine, Brandenburg, Pomerania, Berlin,
Saxony, Schleswig-Holstein, Hannover, Westphalia, Grenzmark Posen-Westpreussen
(now in Poland), Hesse-Nassau, and Hohenzollern (both now in Germany), and Silesia
(now partly in Poland and partly in the Czech Republic). In 1947, after World War II
(1939-1945), Prussia was abolished as a political unit and, with the exception of East
Prussia, partitioned into various parts of the four zones of occupation in Germany,
administered by France, Great Britain, the United States, and the Union of Soviet
Socialist Republics (USSR). The northeastern part of East Prussia was annexed by the
USSR, and the remainder was put under Polish administration. Berlin was the capital,
and the principal cities included Frankfurt am Main, Cologne, Essen, Dortmund,
Düsseldorf, Magdeburg, Stettin (now Szczecin), and Königsberg (now Kaliningrad).

                          Early History
The people from whom the name Prussia is derived were usually called Prussi, or
Borussi, in the earliest sources. They were related to the Lithuanians and inhabited the
region between the Vistula and lower Niemen rivers. The Saxons, a Teutonic people,
entered eastern Europe in the 10th century and failed in their attempts to convert the
Prussians to Christianity. In 997 the Bohemian bishop and saint Adalbert was martyred as
a missionary in Prussia. The Christian faith was not established until about the middle of
the 13th century, when the Teutonic Knights subdued the country and brought German
and Dutch settlers into the conquered territory. By the end of the century the region was
completely subjugated. Thereafter it was ruled by the Teutonic Knights as a papal fief.

During the second half of the 14th century, strong opposition to the Germans developed
in eastern Europe. In 1386 Poland and Lithuania entered into a dynastic union, and in
1410 a Polish and Lithuanian army defeated the Teutonic Knights in the Battle of
Tannenberg. After a further period of warfare, the terms of the second Peace of Thorn, in
1466, left the Knights in possession of the eastern part of Prussia, which it held as a fief
of the Polish crown. Western Prussia was ceded to Poland, becoming known as Polish
Royal Prussia. Eastern Prussia became a secular duchy, known as East Prussia or Ducal
Prussia, under the last grand master of the Teutonic Knights, Albert of Hohenzollern, a
Lutheran, who created himself 1st duke of Prussia in 1525. In 1618 the duchy, still a
vassal state of Poland, passed to John Sigismund, a Hohenzollern; his grandson,
Frederick William, elector of Brandenburg, secured ducal Prussia's independence of
Poland at the Peace of Oliva in 1660. Frederick William centralized the administ
ration of the duchy and assumed governing powers that were formerly exercised by the
nobility and the town oligarchies.

                        Kingdom of Prussia

Frederick William's son, Frederick I, became king of Prussia in 1701, receiving royal
recognition in exchange for a promise of military aid to Holy Roman Emperor Leopold I.
Frederick's son, Frederick William I, greatly increased the size of the Prussian army and
rebuilt the organization of the state around the military establishment. To his son,
Frederick II, the Great, he left enormous financial reserves and the best army in Europe.
Through the military genius of Frederick the Great, Prussia became a major power in
Europe. In 1740 he invaded the Austrian province of Silesia and precipitated the War of
the Austrian Succession.

By the end of the Seven Years' War, in 1763, Prussian territory included Silesia, and in
1772 Frederick annexed Polish Royal Prussia, thus linking his kingdom of Prussia in the
east with Brandenburg and the main body of his German possessions in the west.
Frederick's regime was noted as a model of "enlightened despotism". Frederick William
III succeeded to the throne in 1797 and with the aid of his ministers, Baron vom und zum
Stein and Prince Karl August von Hardenberg, instituted a series of liberal reforms within
the kingdom. From 1801 to 1805, during the Napoleonic Wars, Prussia was dominated by
Napoleon I. In 1806, however, Frederick William joined a coalition against Napoleon.
Frederick William was defeated, and much of his territory was lost. Prussian fortunes
rose after the Battle of Waterloo in 1815 that resulted in the fall of the French Empire.

                    Prussian Dominance in Germany
 
After the negotiations at the Congress of Vienna, Prussia emerged as the major German
power of Western Europe. By 1844 almost all German states were economically linked
with Prussia. Under King William I and his prime minister and imperial chancellor,
Prince Otto von Bismarck, Prussia reached the peak of its power. Bismarck provoked war
with Denmark in 1864, the Seven Weeks' War against Austria in 1866, and the Franco-
Prussian War in 1870. These three wars established Prussia as the leading state in the
German Empire. From then on, Prussia's history generally coincides with that of
Germany. The state of Prussia was legally abolished in 1947 by the Allied Control
Council, a group formed after World War II to resolve issues relating to Germany.