After the war, Graziani was made Viceroy of Italian East Africa and Governor-General of Shewa / Addis Ababa. After an unsuccessful attempt by two Eritreans to kill him on 19 February 1937 (and after murders of other Italians in occupied Ethiopia), Graziani ordered a bloody and indiscriminate reprisal upon the conquered country, later remembered by Ethiopians as "Yekatit 12". Up to thirty thousand civilians of Addis Ababa were killed indiscriminately; another 1,469 were summarily executed by the end of the next month, and over one thousand Ethiopian notables were imprisoned and then exiled from Ethiopia. Graziani became known as "the Butcher of Ethiopia". In connection with the attempt on his life, Graziani authorized the massacre of the monks of the ancient monastery of Debre Libanos and a large number of pilgrims, who had traveled there to celebrate the feast day of the founding saint of the monastery. Graziani's suspicion of the Ethiopian Orthodox clergy (and the fact that the wife of one of the assassins had briefly taken sanctuary at the monastery) had convinced him of the monks' complicity in the attempt on his life.