Der Corregidor is a comic opera by composer Hugo Wolf and librettist Rosa Mayreder adapted from Pedro Antonio de Alarcón's novella El sombrero de tres picos.  It premiered at the Mannheim National Theatre on June 7, 1896.

Mahler's conducting a production of Corregidor would have held great meaning for Wolf had he lived to see it.  The two were close friends, living together prior to Mahler's leaving Vienna to pursue his conducting career.  "[By] the time Mahler returned to Vienna in 1897 to take up the most prestigious post in Viennese music, director of the Court Opera, Wolf was probably the better known composer.  But Wolf's composing career was already at an end.  His last completed songs date from March 1897, and, although he continued to work on his unfinished opera Manuel Venegas, his body and mind were on the verge of collapse" due to syphilis.  It was a meeting with Mahler that would seemingly trigger that collapse.  "Mahler's appointment to the opera had fired Wolf's hopes that his opera Der Corregidor would now at last receive a performance of which Wolf was convinced it was worthy.  He went to see Mahler to press his case...Seeing the score of Anton Rubinstein's opera The Demon on Mahler's desk, Wolf became angry.  He denounced Rubinstein's work.  Mahler responded with some critical comments about Der Corregidor, and expressed doubts about whether it would be performed in Vienna.  This argument was, as Wolf's biographer Frank Walker calls it, 'the spark that had kindled a conflagration in his brain and brought on the long threatened insanity.'" ("Plagued by Mahler," Martin Kettle, The Guardian, February 14 2003.)