ROON, ALBRECHT THEODOR EMIL, COUNT VON (1803-1879), Prussian general field-marshal, was born at Pleus hagen, near Colberg, in Pomerania, on April 3o, 1803. He entered the corps of cadets at Kulm in 1816, proceeded to the military school at Berlin, and in Jan. 1821 joined the 14th (3rd Pomeranian) regiment. In 1826 he was appointed an instructor in the Berlin cadet school, and in 1832 published his Grundziige der Erd-, Volker- and Staaten-Kunde (3 vols.) , gaining a great reputation. This was followed by Anfangsgriinde der Erdkunde (1834), Militarische Liinderbeschreibung von Europa (1837) and Die iberische Halbinsel (1839).
In 1832, he rejoined his regiment, and became alive to the ineffi cient state of the army; in 1842 he was promoted to be major and attached to the staff of the VII. Corps. In 1848 he was appointed chief of the staff of the VIII. Army Corps, and during the dis turbances of that year served under the Crown Prince William (afterwards emperor), distinguishing himself in the suppression of the insurrection at Baden. At that time he broached the subject of his schemes of army reform. In 185o came the revelation of defective organization; next year Roon was made a full colonel and began active work as reorganizer.
Prince William became regent in 1857, and in 1859 he ap pointed Roon (now lieutenant-general) a member of a commis sion to report on military reorganization. Supported by Man teuffel and Moltke, Roon was able to get his plans to create an armed nation, to extend Scharnhorst's system and to adapt it to Prussia's altered circumstances generally adopted. To attain this he proposed a universal three years' service, and a reserve (Landwehr) for the defence of the country when the army was actively engaged. During the Italian War he was charged with
the mobilization of a division. At the end of 1859, though the junior lieutenant-general in the army, he succeeded von Bonin as war minister, and two years later the ministry of marine was also entrusted to him. His proposals of army reorganization met with the bitterest opposition, and it was not until after long fighting against a hostile majority in the chambers that, with Bismarck's aid, he carried the day. Even the Danish campaign of 1864 did not wholly convince the country of the necessity of his measures, and it required the war with Austria of 1866 (when he was promoted general of infantry) to convert obstinate oppo sition into enthusiastic support. After that von Roon became the most popular man in Prussia, and his reforms were ultimately copied throughout continental Europe. His system, adopted after 1866 by the whole North German Confederation, produced its inevitable result in the war with France 187o-71. He was created a count, and in Dec. 1871, succeeded Bismarck as president of the Prussian ministry. Ill-health compelled him to resign in the fol lowing year. He was promoted field-marshal on Jan. 1, 1873, and died at Berlin on Feb. 23, 1879.