In the 1960s Italians, Spanish, Germans, and even Israelis started making their own Westerns, sticking to the classic iconography of gun duels, saloons, and desperadoes on horseback, but without the censorship codes of Hollywood. In the case of Italian director Sergio Leone, there was not just an elevated level of violence, but also a then-groundbreaking filmmaking style, with an emphasis on long, tense close-ups of the actors' faces, widescreen camera compositions, and hauntingly unusual music by Ennio Morricone. Westerns had been jokingly called "horse operas" before. Leone made them something close to real opera, and his style was much imitated.
It also helped that Leone was recommended the lean, little-regarded young actor Eastwood to play his recurring unnamed hero (Morricone originally wanted Henry Fonda or James Coburn), triggering another illustrious career. Though he doesn't come across as all that horrible these days, The Man With No Name was so disturbing to American tastes that when A Fistful of Dollars first aired on U.S. television, the studio hastily shot a prologue (with an Eastwood stand-in with his back to the camera) to explain that he's got a higher purpose than profit -- he's really an undercover lawman being sent on a mission to clean up the town, by guile and stealth. That little addition is missing from the home-video release versions of A Fistful of Dollars. Instead there's just a scrap of incidental dialogue to indicate that the gunslinger empathizes deeply with the victims in San Miguel, not the victimizers.