On 24 December every year, the twelve men of the Brotherhood of St Sebastian in Rheinfelden take the plague lantern from St Martin's Church and, on the stroke of 11 o'clock, proceed through the dark streets of the old town. Wearing black coats and top hats, the men walk in lines of three to each of six fountains in the town. At each, they leave their strict formation to form a circle and sing their Christmas song. At the end of their route, which takes an hour, they join the ecumenical midnight mass service today. On 31 December the tradition is repeated with a New Year song, this time at 9 pm. In recent years this custom has been followed by an organ concert at St Martin's Church.
The Brotherhood of St Sebastian in Rheinfelden was founded in 1541 by twelve citizens of Rheinfelden on the occasion of a repeated outbreak of plague in the town. Since the Middle Ages, Saint Sebastian had been considered the last refuge for plague victims, which is why the brotherhood named itself after him. The brotherhood wanted to help the defenceless population, care for the sick and bury the dead. In a vow, the brotherhood promised to sing a song of thanksgiving at the town fountain on Christmas Eve and New Year's Eve in the hope that God would spare the town from the plague in the coming year. The well singing of the twelve Sebastiani brothers in the silence and darkness of Rheinfelden's old town is still a reminder of the former horrors of the plague.
