Rev. Alban Butler (171173). Volume VII: July. The Lives of the Saints. 1866.
St. Olaus, King of Sweden, Martyr
HE was converted to the faith by St. Anscharius, and for his zeal in propagating the same, and because in the time of a great famine he could not be compelled to offer sacrifice to the idols of Upsal, was sacrificed to them by the rebellious inhabitants of Birca, at that time the usual residence of the kings of Sweden. From the ruins of Birca, Stockholm took its rise, though built at a considerable distance from it. See Puffendorfs History of Sweden, t. 1, p. 70.