Saint Gall, Gallen, or Gallus (c. 550 - c. 646) was an Irish disciple and one of the traditionally twelve companions of Saint Columbanus on his mission from Ireland to the continent. Saint Deicolus is called an older brother of Gall.
Gall and his companions established themselves with Columbanus at first at Luxeuil in Gaul. In 610, he accompanied Columbanus on his voyage up the Rhine River to Bregenz but when in 612 Columbanus traveled on to Italy from Bregenz, Gall had to remain behind due to illness and was nursed at Arbon. He remained in Swabia, where, with several companions, he led the life of a hermit in the forests southwest of Lake Constance, near the source of the river Steinach in cells.
He died around 646-650 in Arbon, and his feast is celebrated on 16 October.
After his death a small church was erected which developed into the Abbey of St. Gall, the nucleus of the Canton of St. Gallen in eastern Switzerland the first abbot of which was Saint Othmar. The monastery was freed from its dependence of the bishop of Constance and Emperor Louis the Pious made it an imperial institution. The "Abbey of St. Gall", (not from the name of its founder and first abbot, but of the saint who had lived in this place and whose relics were honoured there) the monastery and especially its celebrated scriptorium played an illustrious part in Catholic and intellectual history until it was secularized in 1798.
From as early as the 9th century a series of fantastically embroidered Lives of Saint Gall were circulated. Prominent was the story in which Gall delivered Fridiburga from the demon by which she was possessed. Fridiburga was the betrothed of Sigebert II, King of the Franks, who had granted an estate at Arbon (which belonged to the royal treasury) to Gall so that he might found a monastery there. Another popular story about Gall has it that, at the command of the saint, a bear brought wood to feed the fire which Gall and his companions had kindled in the forest.
The fragmentary oldest Life was recast in the 9th century by two monks of Reichenau, enlarged in 816-824 by the celebrated Wettinus, and about 833/884 by Walafrid Strabo, who also revised a book of the miracles of the saint. Other works ascribed to Walafrid tell of Saint Gall in prose and verse. The last is mentioned in Robertson Davies's book "The Manticore", where he interprets the legend in Jungian psychological terms.