Revolution, originally intended for performance during the anniversary year but effectively blocked by Kerzhentsev, who demanded at the work's audition before the Committee on Arts Affairs, "Just what do you think you're doing, Sergey Sergeyevich, taking texts that belong to the people and setting them to such incomprehensible music?" The Cantata was not performed until 5 April 1966, just over 13 years after the composer's death. Forced to adapt to the new circumstances (whatever private misgivings he had about them), Prokofiev wrote a series of "mass songs" (Opp. 66, 79, 89), using the lyrics of officially approved Soviet poets. In 1938, he collaborated with Eisenstein on the historical epic Alexander Nevsky, composing some of his most inventive and dramatic music. Although the film had very poor sound recording, Prokofiev adapted much of his score into a large-scale cantata for mezzo-soprano, orchestra and chorus, which was extensively performed and recorded. In the wake of Alexander Nevsky'''s success, Prokofiev composed his first Soviet opera, Semyon Kotko, which was intended to be produced by the director Vsevolod Meyerhold. The opera's première was postponed because Meyerhold was arrested on 20 June 1939 by the NKVD, and shot on 2 February 1940. At the end of the same year, Prokofiev was commissioned to compose Zdravitsa (literally "Cheers!", but sometimes subtitled Hail to Stalin in English) (Op. 85) to celebrate Joseph Stalin's 60th birthday. Later in 1939, Prokofiev composed his Piano Sonatas Nos. 6, 7, and 8, Opp. 82–84, widely known today as the "War Sonatas". Premiered respectively by Prokofiev (No. 6: 8 April 1940), Sviatoslav Richter (No. 7: Moscow, 18 January 1943) and Emil Gilels (No. 8: Moscow, 30 December 1944), they were subsequently championed in particular by Richter. Biographer Daniel Jaffé argued that Prokofiev, "having forced himself to compose a cheerful evocation of the nirvana Stalin wanted everyone to believe he had created" (i.e. in Zdravitsa) then subsequently, in the three sonatas, "expressed his true feelings". As evidence, Jaffé has pointed out that the central movement of Sonata No. 7 opens with a theme based on the Robert Schumann lied "Wehmut" ("Sadness", from the Liederkreis, Op. 39): its words translate, "I can sometimes sing as if I were glad, yet secretly tears well and so free my heart. Nightingales … sing their song of longing from their dungeon's depth … everyone delights, yet no one feels the pain, the deep sorrow in the song."