Why is Padre Pio famous among so many Italian grandparents today, and why just in Italy?

I get he had the stigmata, but I don't think I've seen any other ethnicity of people worship him like Italian elderly, without fail. Why is he so special for Italian Catholics but not Haitian, or Spanish or Filipino ones?

I get this might border on the "disallowed" side, but I would like to know what happened in the mid 20th Century that propelled him to such stardom in a geographically restraint area. I mean, even the kids of the Fatima sighting (Portuguese) have worldwide acclaim, or at least Catholic Europe-wide acclaim.