Bertold IV of Zähringen founded Fribourg in 1157 as part of his consolidation of regional power, which also saw the establishment of Bern, Burgdorf, Thun and Murten, as well as Freiburg-im-Breisgau northeast of Basel in Germany. After 1218, the Zähringens were succeeded by the Counts of Kyburg, who were themselves bought out by the Austrian Habsburgs in 1277, Fribourg passing from hand to hand with each succession. In 1452, Savoy took over, although in the Burgundian Wars shortly afterwards Fribourg backed the victorious Swiss against Savoy, and so became a free city. In 1481, it joined the Swiss Confederation.For reasons which haven’t been fully explained, Fribourg remained Catholic throughout the Reformation (and is still determinedly Catholic today): virtually surrounded by Protestant Bern, it became a place of refuge for the exiled bishops of Geneva and Lausanne. The oligarchic ruling families retained their grip on power even throughout the 1798 upheavals, and in 1846 Fribourg joined the reactionary Sonderbund, fighting against Protestant liberalism all around. It lost, and suffered expulsion of its Jesuits as revenge. Intolerance was short-lived, though: Jews were allowed to return to Fribourg in 1866 after almost 400 years of banishment from the city, and a local entrepreneur, Georges Python, founded the Catholic university in 1889.