Eleanora Ehrenberg stared in what opera that was first performed at the Provisional Theatre, Prague in 1866?
Eleanora Ehrenbergů:  In 1866 she created the role of Mařenka in the world première of Bedřich Smetana's "The Bartered Bride", and in 1868 she portrayed Jitka in the premiere of Smetana's "Dalibor". The Bartered Bride:  It was composed during the period 1863–66, and first performed at the Provisional Theatre, Prague, on 30 May 1866 in a two-act format with spoken dialogue.
The Bartered Bride