 For the opening performance, it was intended that the soloists should be Galina Vishnevskaya (a Russian), Peter Pears (an Englishman) and Dietrich Fischer-Dieskau (a German), to demonstrate a spirit of unity.Close to the premiere, the Soviet authorities did not permit Vishnevskaya to travel to Coventry for the event, although she was later permitted to leave to make the recording in London.With only ten days' notice, Heather Harper stepped in and performed the soprano role.