Which sect of Christianity is the second most dominant in Italy?

Answer 1

Most dominant is Catholicism and then depending on definition of a sect, Wikipedia says,

''At the beginning of 21st century, there were more than

700,000 Eastern Orthodox Christians in Italy,

including 180,000 Greek Orthodox,

550,000 Pentecostals and Evangelists (0.8%),

of whom 400,000 are members of the Assemblies of God,

235,685 Jehovah's Witnesses (0.4%),

30,000 Waldensians,

25,000 Seventh-day Adventists,

22,000 Mormons,

15,000 Baptists (plus some 5,000 Free Baptists),

7,000 Lutherans,

4,000 Methodists (affiliated with the Waldensian Church''