The Utraquists obtained (1436) royal recognition of the Compactata, which remained the fundamental religious law of Bohemia until 1567. By that time Protestantism had made great progress in Bohemia, and the Utraquists themselves were divided. The Old Utraquists remained Catholic; the New Utraquists joined with the Lutherans and drew up (1575) the Confessio Bohemia, which achieved official status (1609) in the Letter of Majesty of Emperor Rudolph II (see Bohemia). The violation of this letter was the prelude to the Thirty Years War. Bohemia, which was overwhelmingly Protestant in the mid-16th cent., was returned to Catholicism by both force and persuasion. Nevertheless, the Evangelicals, as the Lutheran Utraquists were called, did not entirely disappear, and neither did the other major communion, the Moravian Church.