Complex sentence: Its première took place (in an Italian translation) in January 1957 at La Scala in Milan; premières in Paris, France in French and in the United States (in English translation) in San Francisco followed the same year.
Split into simpler sentences: Its première took place (in an Italian translation) in January 1957 at La Scala in Milan. The French première in Paris, sung in French, and the United States première, in English translation, in San Francisco followed the same year.