Two of his paternal great-great-grandparents were German immigrants. Kimmel's mother is of Italian ancestry from Ischia, Naples her family migrated to the United States after the 1883 earthquake.
He was raised Catholic and, as a child, was an altar server. Kimmel was born in Brooklyn, New York, and grew up in the neighborhood of Mill Basin as the eldest of three children of Joan (Iacono) and James John Kimmel, who worked at American Express and was an IBM executive.
