As the preface to my source notes, "The religious guild of Corpus Christi was established in York in the year 1408 by 'chaplains and other worthy parsons, both secular and regular', and dedicated 'to the praise and honour of the most sacred body of Our Lord Jesus Christ'. The principal object of its founders appears to have been to promote the decorous observance of the religious festival of Corpus Christi, and to provide for the due performance of the ceremonies of the day".