Passage: Following the capture of Rome in 1870 from French forces of Napoleon III, Papal troops and Zouaves, relations between Italy and the Vatican remained sour for the next sixty years with the Popes declaring themselves to be prisoners in the Vatican. The Roman Catholic Church frequently protested the actions of the secular and anticlerical-influenced Italian governments, refused to meet with envoys from the King and urged Roman Catholics not to vote in Italian elections. It would not be until 1929 that positive relations would be restored between the Kingdom of Italy and the Vatican after the signing of the Lateran Pacts.

Question: How many years was the relationship between the Vatican and Italy sour?
sixty years