The plygain service is thought to have been created to replace the traditional Latin pre-Reformation Mass at Cockcrow (missa in gallicantu).
[1] In 1830s Marford, they decorated the farmhouse with winter foliage such as holly or mistletoe, and in 1774, in Dyffryn Clwyd, they lit the candles at two o'clock in the morning and sang and danced to harp music until the dawn service.
[1] Candles were decorated with coloured paper and hoops woven by local congregants, and some parishes would fix them to brass candlesticks on the altar before Plygain began.
[1] The ceremony was described as follows:Now the church is in a blaze, now crammed, body, aisles, gallery, now Shon Robert, the club-footed shoemaker, and his wife, descending from the singing seat to the lower and front part of the gallery, strike up alternately, and without artificial aid of pitch pipe, the long, long carol and old favourite describing the Worship of Kings and of the Wise Men, and the Flight into Egypt, and the terrible wickedness of Herod.
Then the good Rector, and his curate, David Pugh, stand up, and read the Morning Service abbreviated, finishing with the prayer for All Conditions of Men, and the benediction restless and somewhat surging is the congregation during prayers the Rector obliged sometimes to stop short in his office and look direct at some part or persons, but no verbal admonishment.
Prayers over, the singers begin again more carols, new singers, old carols in solos, duets, trios, choruses, then silence in the audience, broken at appropriate pauses by the suppressed hum, of delight and approval, till between eight and nine, hunger telling on the singers, the Plygain is over and the Bells strike out a round peal.In Maentwrog, near Blaenau Ffestiniog, there was a very short sermon as part of the service, and the church was decorated with candles fixed to the top of posts, which were themselves fastened to pews.
[1] When they arrived at the church, it was lit with hundreds of candles placed only a couple of inches apart, making for a "brilliant" display.
[1] This sort of display was a key part of many local plygain ceremonies, as it left a strong impression in the written records that remain.
[6] In 2006 a recording of an early twentieth century plygain was discovered at the British Library by Wyn Thomas of the University of Wales, Bangor.