From today's Washington Post:

"Anis Amri, the 24-year-old Tunisian who was fatally shot in a standoff with police early today in Italy, had pledged allegiance to Abu Bakr al-Baghdadi, a self-proclaimed “caliph” of the Islamic State, according to a video released by a news agency linked to the group."

Apparently, he missed the memo about it not being about religion.