William I, 1797-1888, emperor of Germany (1871-88) and king of Prussia (1861-88), second son of the future King Frederick William III of Prussia and Louise of Mecklenburg. Essentially conservative, William fled to England during the revolutionary uprisings of 1848 in Prussia, and upon his return (1849) he commanded the troops that crushed the republican insurrection in Baden. When his brother King Frederick William IV was declared insane, William became (1858) regent, and on Frederick William's death William became king of Prussia. William immediately set about reorganizing and strengthening the army, and when he met the opposition of the legislature, he appointed Otto von Bismarck his prime minister in 1862. From then until the emperor's death, Bismarck guided the destiny of Prussia and Germany. Opposition to the king's and Bismarck's military program was suppressed, and in 1864 Prussia began its career of military conquest in the war with Denmark over Schleswig-Holstein. This led to the Austro-Prussian War of 1866, from which Prussia emerged the leading German power. William I commanded in person in the Franco-Prussian War of 1870-71, received the surrender of Napoleon III at Sedan, and was proclaimed (Jan. 18, 1871) emperor of Germany in the Hall of Mirrors at Versailles (see Germany). Although William often disagreed with Bismarck's policies, he ultimately was always persuaded by his chancellor. William did not favor the Kulturkampf (Bismarck's struggle against the Roman Catholic Church) but gave it his tacit consent. As a symbol of reborn German unity he was popular, but his militarism and belief in his divine right to rule drew upon him the hatred of the radical elements. Two attempts on William's life (1878) enabled Bismarck to pass severe legislation against the socialists. William's reign was crucial in European history, for it saw Germany's rise to power on the continent. His son Frederick III succeeded him.

William I or William the Conqueror, 1027?-1087, king of England (1066-87). Earnest and resourceful, William was not only one of the greatest of English monarchs but a pivotal figure in European history as well.

Duke of Normandy

The illegitimate son of Robert I, duke of Normandy, and Arletta, daughter of a tanner, he is sometimes called William the Bastard. He succeeded to the dukedom on his father's death in 1035. William and his guardians were hard pressed to keep down recurrent rebellions during his minority, and at least once the young duke barely escaped death.

In 1047, with the aid of Henry I of France, he solidly established his power. William is said to have visited England in 1051 or 1052, when his cousin Edward the Confessor probably promised that William would succeed him as king of England. Despite a papal prohibition, William married Matilda, daughter of Baldwin, count of Flanders, in 1053. The union, which greatly increased the duke's prestige, did not receive papal dispensation until 1059.

William's growing power brought him into conflict with King Henry of France, whose invading armies he defeated in 1054 and 1058. The accession (1060) of the child Philip I of France, whose guardian was William's father-in-law, improved his position, and in 1063 William conquered the county of Maine. Soon afterward Harold, then earl of Wessex, was shipwrecked on the French coast and was turned over to William, who apparently extracted Harold's oath to support the duke's interests in England.

King of England

The Norman Conquest

Upon hearing that Harold had been crowned (1066) king of England, William secured the sanction of the pope, raised an army and transport fleet, sailed for England, and defeated and slew Harold at the battle of Hastings (1066). Overcoming what little resistance remained in SE England, he led his army to London, received the city's submission, and was crowned king on Christmas Day.

Although William immediately began to build and garrison castles around the country, he apparently hoped to maintain continuity of rule; many of the English nobility had fallen at Hastings, but most of those who survived were permitted to keep their lands for the time being. The English, however, did not so readily accept him as their king.

A series of rebellions broke out, and William suppressed them harshly, ravaging great sections of the country. Titles to the lands of the now decimated native nobility were called in and redistributed on a strictly feudal basis (see feudalism), to the king's Norman followers. By 1072 the adherents of Edgar Atheling and their Scottish and Danish allies had been defeated and the military part of the Norman Conquest virtually completed. In the only major rebellion that came thereafter (1075), the chief rebels were Normans.

Later Reign

William undertook church reform, appointed Lanfranc archbishop of Canterbury, substituted foreign prelates for many of the English bishops, took command over the administration of church affairs, and established (1076) separate ecclesiastical courts. In 1085-86 at his orders a survey of England was taken, the results of which were embodied in the Domesday Book. By the Oath of Salisbury in 1086, William established the important precedent that loyalty to the king is superior to loyalty to any subordinate feudal lord of the kingdom. William fought with his factious son Robert II, duke of Normandy, in 1079 and quarreled intermittently with France from 1080 until his death. He invaded the French Vexin in 1087, was fatally injured in a riding accident, and died at Rouen, directing that his son Robert should succeed him in Normandy and his son William (William II) in England.

William I, 1772-1843, first king of the Netherlands and grand duke of Luxembourg (1815-40), son of Prince William V of Orange, last stadtholder of the Netherlands. He commanded (1793-95) the Dutch army in the French Revolutionary Wars, and after the French occupation of the Netherlands he entered the Prussian and later the Austrian service. He returned to the Netherlands in 1813, and the Congress of Vienna gave him (1815) the title king of the Netherlands. His kingdom comprised present Belgium as well as the Netherlands, and he was awarded the grand duchy of Luxembourg in compensation for his family holdings in Germany, which he ceded to Prussia. William soon alienated his Belgian subjects by attempting to make Dutch the official language, by granting disproportionate influence to the northern provinces, and by encroaching on the freedom of the Roman Catholic Church. Political unrest in Belgium led to the revolution of 1830, which he stubbornly sought to suppress despite the intervention of England and France (see London Conference). Belgium won its independence, but final recognition by William came only in 1839. When his Dutch subjects forced him to liberalize the constitution in 1840, he abdicated in favor of his son William II. Through his rule as an enlightened despot, William fostered the development of Dutch agriculture, commerce, and industry.

William I, 1781-1864, king of Württemberg (1816-64), son and successor of Frederick I. Before his accession he fought (1812) with the French emperor Napoleon I in Russia and later, when Frederick I had broken his alliance with France, William served with the anti-French forces (1814-15). As king, William granted a constitution in 1819, strove to protect the rights of the smaller German states against both Austria and Prussia, and promoted the Zollverein, the German customs union.

William I, prince of Orange: see William the Silent.

Frederick William I, 1688-1740, king of Prussia (1713-40), son and successor of Frederick I. He continued the administrative reforms and the process of centralization begun by Frederick William, the Great Elector, creating a strong, absolutist state. He practiced rigid economy, and at his death there was a large surplus in the treasury. The Prussian army was made an efficient instrument of war. Although Frederick William built up one of the most powerful armies in Europe, he was essentially a peaceful man. He intervened briefly in the Northern War, but gained little territory. Later, he signed a treaty (1728) with Holy Roman Emperor Charles VI in the hope of acquiring the territories of Jülich and Berg, to which he had a hereditary claim. The emperor subsequently went back on this agreement. Frederick William was a coarse man, and he had contempt for his gifted heir, who was to succeed him as Frederick II (Frederick the Great).

known as William the Conqueror

(born circa 1028, Falaise, Normandy—died Sept. 9, 1087, Rouen) Duke of Normandy (1035–87) and king of England (1066–87). Though born out of wedlock, he succeeded his father as duke of Normandy, subduing rebellions and becoming the mightiest noble in France. In 1051 Edward the Confessor promised to make him heir to the English throne, but on Edward's death in 1066, Harold Godwineson, earl of Wessex (Harold II), was accepted as king. Determined to assert his right to the throne, William sailed from Normandy with an invasion force, defeated Harold at the Battle of Hastings, and was crowned king. The Norman Conquest was thus completed, though English rebellions continued until 1071. To secure England's frontiers, William invaded Scotland (1072) and Wales (1081). In 1086 he ordered the survey summarized in the Domesday Book. He divided his lands between his sons, giving Normandy and Maine to Robert II and England to William II.

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German Friedrich Wilhelm

(born Aug. 15, 1688, Berlin—died May 31, 1740, Potsdam, Prussia) King of Prussia (1713–40). The son of Frederick I, he received valuable military experience in the War of the Spanish Succession. Realizing that Prussia's military and financial weakness made it dependent on the relations between the great powers, he built up an army that became a strong military presence on the Continent, instituted economic and financial reforms, centralized his administration, encouraged industry and manufacture, mandated compulsory primary education (1717), and freed the serfs on his own domains (1719). He was succeeded by his son, Frederick II.

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