The subject of Mahler performances in the midwest has surfaced in the discussion of how and why Mercury might not have recorded Mahler.
A check of Antal Dorati's Mahler performances with the Minneapolis Symphony Orchestra from 1950-1960, given in Richard Chlupaty, Antal Dorati and the Joy of Music Making (Romsey, Engl.: BAS Printers, 2006) suggests that Mahler was performed in Minneapolis with fair frequency, indeed, especially in the 1950 season, then through 1955, but strangely, not from 1955-60.
1950: Mahler, Sym No. 3, with Elaine Dahlgren Schuessler and the Cecilian Singers and Boys from St. John's Church, St. Paul (Schuessler was a regionally known contralto)
1950: Mahler, Lieder eines Fahrenden Gesellen, with Blanche Thebom
1950: Mahler, Kindertotenlieder, with Marian Anderson
1952: Mahler, Sym No. 1
1954: Mahler, Sym No. 2, with University of Minnesota Chorus, Laurel Hurley, and Lucretia West
1955: Mahler, Das Lied von der Erde, with Elena Nikolaida and Set Svanholm
This is not to suggest that Mercury erred in its recording program with Dorati and the Minneapolis Symphony. Their Tchaikovsky recordings were huge successes, artistically, acoustically, and commercially. Dorati's Beethoven won plaudits too, especially his Eroica, a long-ago predecessor to Osmo Vänskä's success with the full set of Beethoven symphonies.