On 2 September 1642, just after the First English Civil War had begun, the Long Parliament ordered the closure of all London theatres.
The order cited the current "times of humiliation" and "sad and pious solemnity", a zeitgeist incompatible with "public stage-plays", which were representative of "lascivious Mirth and Levity".
[1] The closure was the culmination of the rising anti-theatrical sentiment among Puritans, and along with William Prynne's Histriomastix (1633), its text was the most notorious attack on theatre in English history.
Another Act of 11 February 1648, at the beginning of the Second Civil War, was "a much more severe decree"; it provided for the treatment of actors as rogues, the demolition of theatre seating, and fines for spectators.
[1] In 1660, after the English Restoration brought King Charles II to effective power in England, the theatrical ban was lifted.