The pataria was an eleventh-century Catholic movement focused on the city of Milan in northern Italy, which aimed to reform the clergy and ecclesiastic government within the city and its ecclesiastical province, in support of papal sanctions against simony and clerical marriage. Those involved in the movement were called patarini, patarines or patarenes, a word perhaps chosen by their opponents, the etymology of which is uncertain. The movement, associated with urban unrest in the city of Milan, is generally considered to have begun in 1057 and ended in 1075.

Bogomilism was a Christian neo-Gnostic, dualist sect founded in the First Bulgarian Empire by the priest Bogomil during the reign of Tsar Peter I in the 10th century. It most probably arose in the region of Kutmichevitsa, today part of the region of Macedonia.