The Ministry of War (German: Kriegsministerium) was a ministry for military affairs of the Kingdom of Bavaria, founded as Ministerium des Kriegswesens on October 1, 1808 by King Maximilian I Joseph of Bavaria. It was located at Ludwigstraße in Munich. Today the building, that was built by Leo von Klenze between 1824 and 1830, houses the Bavarian public record office, named Bayerisches Hauptstaatsarchiv und Staatsarchiv München.

The ministry was the successional institution of the royal Bavarian Hofkriegsrat (court war council, founded in 1620) and its follow-on institutions, that were responsible for the military:

The name of the Ministerium des Kriegswesens changed to Staatsministerium der Armee in 1817, and at last to Kriegsministerium in 1825.

From 1801 to 1817, King Maximilian I Joseph of Bavaria by himself held the fully command of the Bavarian Army. In 1817 general Von Triva was made the real head of the Ministry by him, but the administration of justice and economics of the military was part of the Oberadministrativkollegium and the Generallazarettinspektion. In 1822 Maximilian I assigned general Von Wrede as commander-in-chief of the army, and the Staatsministerium der Armee became also responsible for the administration of justice and economics. After 1829 the tasks and responsibilities of the supreme command of the army (Oberkommando, existing from 1822 to 1829) were transferred to the Minister of War, so that he was additionally commander-in-chief of the army. Compared to ministers of other countries, e. g. the Prussian minister, the Bavarian war minister had much more competences, after he got also the command of the army. After the breakdown of the Bavarian kingdom in 1918, the Kriegsministerium was replaced by the Ministerium für militärische Angelegenheiten (ministry of military affairs).

Bavaria, formally the Free State of Bavaria (German: Freistaat Bayern, pronounced [ˈfʁaɪʃtaːt ˈbaɪ.ɐn] ( listen)), is a state of Germany, located in the southeast of Germany. With an area of 70,548 square kilometres (27,200 sq mi), it is the largest state by area, forming almost 20% of the total land area of Germany. Bavaria is Germany's second most populous state (after North Rhine-Westphalia), with 12.5 million inhabitants, more than any of the three sovereign states on its borders. Bavaria's capital is Munich.

One of the oldest states of Europe, it was established as a duchy in the mid first millennium. In the 17th century, the Duke of Bavaria became a Prince-elector of the Holy Roman Empire. The Kingdom of Bavaria existed from 1806 to 1918, and Bavaria has since been a free state (republic). Modern Bavaria also includes parts of the historical regions of Franconia and Swabia.

The Bavarians emerged in a region north of the Alps, originally inhabited by the Gauls, which had been part of the Roman provinces of Raetia and Noricum. The Bavarians spoke Old High German but, unlike other Germanic groups, probably did not migrate from elsewhere. Rather, they seem to have coalesced out of other groups left behind by Roman withdrawal late in the 5th century. These peoples may have included the Celtic Boii, some remaining Romans, Marcomanni, Allemanni, Quadi, Thuringians, Goths, Scirians, Rugians, Heruli. The name "Bavarian" ("Baiuvarii") means "Men of Baia" which may indicate Bohemia, the homeland of the Celtic Boii and later of the Marcomanni. They first appear in written sources c. 520. Saint Boniface completed the people's conversion to Christianity in the early-8th century. Bavaria was, for the most part, unaffected by the Protestant Reformation.

A Ministry of War or Ministry for War is an administrative, supply and services agency of an army, as opposed to the entire military establishment. Both Mexico and Brazil (until 1999) both still maintain a War Department for the support of their armies. Ministries of War were generally replaced by a unified Ministry of Defense to support all military services.