What common genesis is shared by each of the three following Broadway stage productions :
Annie
Shenandoah
Man of La Mancha ?

"The Goodspeed Opera House is the birthplace of some the world's most famous musicals, including Annie, Man of La Mancha and Shenandoah. The opera house was originally built by a local merchant and banker, William Goodspeed. Construction began in 1876 and finished in 1877. Despite the name, it was not in fact an opera house, but rather a venue for presenting plays"
Source:
http://en.wikipedia.org/wiki/Goodspeed_Opera_House

Yes indeedily !

Thanks for the answer !