Naples, like the other portions of southern Europe, had been exposed to the infection of heresy. At an early period missionaries from Bulgaria had penetrated the passes of the southern Apennines, and, in that motley population of Greek and Saracen and Norman, proselytes had not been lacking. The Norman kings, usually at enmity with the Holy See, had not cared to inquire too closely into the orthodoxy of their subjects, and had they done so the independence of the feudal baronage would have rendered minute perquisition by no means easy. The allusions of the Abbot Joachim of Flora to the Cathari indicate that their existence and doctrines were familiar facts in Calabria, though as Rainerio makes no allusion to any Catharan church in Italy south of Florence it is presumable that the sectaries were widely scattered and unorganized. In 1235, when the Dominican convent in Naples was broken into by a mob and several of the friars were grievously wounded, Gregory IX. attributed the violence to friends of heretics.[274] Frederic II., however much at times his policy might lead him to proclaim ferocious edicts of persecution, and even spasmodically to enforce them, had no convictions of his own to render him persistent in persecution, and his lifelong contest with the papacy gave him, secretly at least, a fellow-feeling with all who resisted the supremacy of the Holy See, whether in temporal or spiritual concerns. Occasional attacks such as that under the auspices of the Archbishop of Reggio, in 1231, or the form of secular inquisition which he instituted in 1233, had little permanent effect. Cathari driven from Languedoc, who perhaps found even Lombardy insecure, were tolerably sure of refuge in the wild and secluded valleys of Calabria and the Abruzzi, lying aside from the great routes of travel. The domination in Naples of Innocent IV. was too brief for the organization of any systematized persecution, and when Manfred reconquered the kingdom, although he seems to have felt his position too precarious to risk open toleration, and, under pressure from Jayme of Aragon, he ordered Bishop Vivian of Toulouse and his disciples, who had settled in Apulia, to leave his dominions, yet he went no further in active measures of repression.[275]