Mussical theatre was actually an accident. there was a play going on in new york in 1866 called 'The Black Crook'. The producers thought it needed more pazzas.
Meanwhile, a ballet was going on down the street. it was opening night but before it opened the theatre was burned down.
In order to save both shows, they mixed both productions together. yes, the audience was surpised,but they loved it. New york came out with some new productions and musical theatre was born!
Yes, everything in this article is ture. i know, i was suprised too.