Carlo Tresca was born on March 9, 1879 in Sulmona, Abruzzi, Italy. He the third son and fourth of eight children of Filippo and Filomena (Faciano) Tresca. Both parents came from established wealthy families. When Carlo was still young, however, his father, who managed the family estate and engaged in business ventures and local politics, lost the ancestral lands and home through speculative investments.
An unruly and pugnacious youth, he later attributed his lifelong rebellion against authority to his father's domineering character.