Conradin Kreutzer or Kreuzer (Messkirch in Baden, November 22, 1780– Riga, December 14, 1849, Riga) was a German composer and conductor. His works include the opera for which he is remembered, Das Nachtlager in Granada, and Der Verschwender, both produced in 1834.
Kreutzer owes his fame almost exclusively to Das Nachtlager von Granada (1834), which kept the stage for half a century in spite of changes in musical taste. It was written in the style of Carl Maria von Weber, and is remarkable especially for its flow of genuine melody and depth of feeling. The same qualities are found in Kreutzer's part-songs for men's voices, which at one time were extremely popular in Germany, and are still listened to with pleasure. Among these Das ist der Tag des Herrn ("The Lord's Day") may be named as the most excellent. His Septet for winds and strings, Op. 62, remains in the chamber music repertory.
Kreutzer abandoned his studies in the law and went to Vienna about 1804, where he met Haydn and may have studied with Albrechtsberger, while he tried his hand unsuccessfully at singspielen. He spent 1811-12 in Stuttgart, where at least three of his operas were staged and he was awarded the post of Hofkapellmeister. Once he was successful, he became a prolific composer, and wrote a number of operas for the Theater am Kärntnertor and other theatres in Vienna, which have disappeared from the stage and are not likely to be revived. He was from 1812 to 1816 Kapellmeister to the king of Württemberg, and in 1840 became conductor of the opera at Cologne. His daughter, Cecilia Kreutzer, was a singer of some renown.
Martin Heidegger's Memorial Address, given on the occasion of the anniversary of Kreutzer's birth in their home town, registers the philosopher's enthusiasm for Kreutzer's work and legacy. The Address is notable for presenting in a way non-academics could understand Heidegger's distinction between calculative and meditative thinking and his ideas about the importance of autochthony to creative work and meditative thinking.