Vinzenz Lachner (also spelled Vincenz) (19 July 1811 – 22 January 1893) was a German composer and conductor.
Born in Rain am Lech, Vinzenz was the youngest brother of Franz Lachner, also a composer and conductor. The elder Lachner was known as a close friend of composer Franz Schubert. As a composer Vinzenz was essentially self-taught. He was first educated by his father Anton Lachner, the municipal organist. After Anton's death, Vinzenz was schooled in Augsburg.
Vinzenz scratched out a living by teaching music in Augsburg until his brother Franz arranged for him to become conductor and house musician for Earl Mycielski of Coscevitz in the Grand Duchy of Posen. In 1831 he moved to Vienna to continue his musical training, becoming assistant conductor at the Court Opera and organist at a Protestant church (though he himself was Catholic). In 1836 he became court conductor at Mannheim in succession to Franz, where he was so highly valued that his contract was renewed and extended whenever he received offers from other musical centres. In all he remained there for 37 years, during which Mannheim had the reputation of performing the largest repertoire of operas of any city in Germany. Nevertheless, Lachner travelled and conducted widely, as far afield as London.
As an educator, he encountered and encouraged many. His students included Fritz Steinbach. Lachner encouraged a number of prominent younger musicians, notably Max Bruch, Hermann Levi, and Carl Wolfsohn. See: List of music students by teacher: K to M#Vinzenz Lachner.
Instinctively conservative in his tastes, Lachner stood out publicly against the cult of Richard Wagner, but the formation of a Wagner Association in Mannheim at the beginning of the 1870s was the beginning of the end for his career. Wagner himself came to conduct in Mannheim. Having already engineered the removal of Franz Lachner from Munich, Wagner campaigned for Vinzenz Lachner to be retired. (Vinzenz, to Wagner's rage, had conducted Wagner's opera The Flying Dutchman in a mutilated version.)