 On this so-called "Hellfeiertag" (roughly “Light Holiday” – despite the similarity in pronunciation, there is no connection with “hellfire”), the Friday before Michaelmas, it was forbidden to light a fire in any hearth, and both people and livestock observed a strict fast and did no work.The vow was strictly kept right up until the First World War.As early as the 12th century, Glattbach was mentioned as a branch of Saint Agatha's parish at Aschaffenburg.