Whitsun (Sulgwyn) is recorded in the Laws of Hywel Dda as one of the three main holidays of the medieval Welsh kingdoms, the others being Christmas (Nadolyg) and Easter (Pasc).
Whitsun traditions in Wales;
* In areas of south and east Wales the Church used to organise an outdoor feast called the Whitsun Ale after the specially brewed ale that was provided. A Lord and Lady of the Ale would often be elected to preside over the festivities, which included music, dancing, sports and games. These were later replaced by fairs and parades in some areas.
* A custom once held on Llŷn peninsula was where couples desiring future happiness tried to pass through a divided tree called Y Pren Dedwydd (The Blessed Tree).
The CHURCH organized ale parties and dancing?
The dancing was led by the bonnie lass of Anglesey, I bet.
Syncretism at its finest.