Answer: "A Life for the Tsar"
More information: Originally entitled "Ivan Susanin", Mikhail Glinka renamed the first of his two most-famous operas to "A Life for the Tsar" (1836) as a show of favor to Emperor Nicholas I who monitored the work while it was in progress and is said to have actually suggested the name change.
Did we miss something? Is the answer wrong? Please, let us know about it through our feedback box