Ludwig I or Louis I (German: Ludwig I.; 25 August 1786 – 29 February 1868) was King of Bavaria from 1825 until the 1848 revolutions in the German states. When he was crown prince, he was involved in the Napoleonic Wars. As king, he encouraged Bavaria's industrialization, initiating the Ludwig Canal between the rivers Main and the Danube. In 1835, the first German railway was constructed in his domain, between Fürth and Nuremberg, with his Bavaria joining the Zollverein economic union in 1834. After the July Revolution of 1830 in France, Ludwig's previous liberal policy became increasingly repressive; in 1844, Ludwig was confronted during the Beer riots in Bavaria. During the revolutions of 1848 he faced increasing protests and demonstrations by students and the middle classes. On 20 March 1848, he abdicated in favour of his eldest son, Maximilian.
Ludwig lived another 20 years after his abdication and remained influential. An admirer of ancient Greece and the Italian Renaissance, he patronized the arts and commissioned several neoclassical buildings, especially in Munich. He was an avid collector of arts, amassing paintings from the Early German and Early Dutch periods as well as Graeco-Roman sculptures.