Original: The reform was largely carried out by Saint Odo ( c. 878 -- 942 ) and spread through France ( Burgundy , Provence , Auvergne , Poitou ) , England , and much of Italy and Spain.Justus.Anglican.org Corruption The impetus for the reform was corruption within the church , particularly simony and concubinage .
Simplified: The reform was largely carried out by Saint Odo . It spread through France ( Burgundy , Provence , Auvergne , Poitou ) , England and much of Italy and Spain .