WILLIAM I (1797-1888), king of Prussia and German emperor, was the second son of Frederick William III. of Prussia and Louisa, a princess of Mecklenburg-Strelitz. He was born at Berlin on 22d March 1797, and received the names of Wilhelm Friedrich Ludwig. He was a delicate child and had to be carefully nurtured. His constitution, however, was sound, and he became one of the most vigorous men in Germany. After the battle of Jena he spent three years at Königsberg and Hemel. Meanwhile he had given evidence of sterling honesty, a strict love of order, and an almost passionate interest in everything relating to war. On 1st January 1807 he received an officer's patent, and on 30th October 1813 was appointed a captain. William accompanied his father in the campaign of 1814, and early in the following year received the iron cross for personal bravery shown at Bar-sur-Aube. He took part in the entry into Paris on 31st March 1814, and afterwards visited London. He joined the Prussian army in the final campaign of the Napoleonic wars, and again entered Paris. The prince was made a colonel and a member of the permanent military commission immediately after his twentieth birthday, and at the age of twenty-one became a major-general. In 1820 he received the command of a division; and during the following nine years he not only made himself master of the military system of his own country but studied closely those of the other European states. In 1825 he was promoted to the rank of lieutenant-general, and obtained the command of the corps of guards. On 11th June 1829 he married Augusta of Saxe-Weimar. On the death of his father ih 1840the new king, Frederick William IV., being childlessPrince William, as heir presumptive to the throne, received the title of prince of Prussia. He was also made lieutenant-governor of Pomerania and appointed a general of infantry. In politics he was decidedly Conservative ; but at the outbreak of the revolutionary movement of 1848 he saw that some concessions to the popular demand for liberal forms of government were necessary. He urged, however, that order should be restored before the establishment of a constitutional system. At this time he was the best-hated man in Germany, the mass of the Prussian people believing him to be a vehement supporter of an absolutist and reactionary policy. He was even held responsible for the blood shed in Berlin on 18th March, although he had been relieved nine days before of his command of the guards. So bitter was the feeling against him that the king entreated him to leave the country for some time, and accordingly he went to London, where he formed intimate personal relations with Prince Albert, Sir Robert Peel, Lord John Russell, Lord Palmerston, and other English statesmen. On 8th June he was back at Berlin, and on the same day he took his seat as member for Wirsitz in the Prussian national assembly, and delivered a speech in which he expressed belief in constitutional principles. In 1849, when the revolutionary party in the grand-duchy of Baden became dangerous, he accepted the command of the army of operation in Baden and the Palatinate," and his plans were so judiciously formed and so skilfully executed that in the course of a few days the rebellion was crushed. At the beginning of the campaign an unsuccessful attempt was made on his life. In October 1849 he was appointed military governor of the Rhineland and Westphalia, and took up his residence at Coblentz. In 1854 the prince was raised to the rank of a field-marshal and made governor of the confederate fortress of Mainz. When the king was attacked with a disease of thè brain, Prince William assumed the regency (7th October 1858).
On 2nd January 1861 Frederick William IV. died, and his brother succeeded him as William I. For the internal conflict between the king and the house of representatives on the question of military reorganization, which filled up the first years of his reign, see GERMANY (vol. x. p. 510) and PRUSSIA (vol. xx. p. 12). The events and results of the war with Denmark, and of that with Austria which arose out of the Schleswig-Holstein question, belong to the history of Austria and of Prussia, and have been already described under those articles. The brilliant achievements of the army in this last contest finally convinced the king's subjects that his aims had been wise. On his return to Berlin he was received with unbounded enthusiasm, and from this time he was looked up to as a father rather than as a sovereign. On the outbreak of the war with France in 1870 all Germans rallied round the king of Prussia, and, when on 31st July he quitted Berlin to join his army, he knew that he had the support of a united nation. He crossed the French frontier on the 11th of August, and personally commanded at the battles of Gravelotte and Sedan. It was during the siege of Paris, at his head-quarters in Versailles, that he was proclaimed German emperor on 18th January 1871. On 3d March 1871 he signed the preliminaries of peace which had been accepted by the French assembly; and on 21st March he opened the first imperial parliament of Germany. On 16th June he triumphantly entered Berlin at the head of his troops.
After that period the emperor left the destinies of Germany almost entirely in the hands of Bismarck, who held the office of imperial chancellor (see PRUSSIA). In his personal history the most notable events were two attempts upon his life in 1878,one by a working lad called Hodel, another by an educated man, Karl Nobiling. On the first occasion the emperor escaped without injury, but on the second he was seriously wounded. These attacks grew out of the socialist agitation ; and a new reichstag, elected for the purpose, passed a severe anti-socialist law, which was afterwards from time to time renewed. The socialists, however, far from being crushed, again and again gave proof of their power by returning a considerable number of deputies to parliament. In the hope of alienating from them the mass of the working class, Bismarck introduced, with the cordial approval of the emperor, a series of measures for the benefit of the poorer members of the community. Until within a few days of his death the emperor's health was remarkably robust; he died at Berlin on 9th March 1888.
The reign of William I. marked an era of vast importance in the history of Germany. In his time Prussia became the first power in Germany and Germany the first power in Europe. These momentous changes were due in a less degree to him than to Bismarck and Moltke ; but to him belongs the credit of having recognized the genius of these men, and of having trusted them absolutely. Personally William was a man of a singularly noble and attractive character. His supreme wish was to discharge loyally the duties which had been imposed upon him, and he never shrank from any personal sacrifice that seemed to be demanded in the interests of his people. The best traditions of the Hohenzollerns were maintained, not only by the splendour of the achievements with which his name will always be intimately associated, but by the simplicity, manliness, and uprightness of his daily life.