Where did a subgenre of Western films, Spaghetti Western originate?

Spaghetti Western, also known as Italian Western or Macaroni Western (primarily in Japan), is a broad subgenre of Western films that emerged in the mid-1960s in the wake of Sergio Leone's film-making style and international box-office success. The term was used by American critics and those in other countries because most of these Westerns were produced and directed by Italians.

According to veteran Spaghetti Western actor Aldo Sambrell, the phrase "Spaghetti Western" was coined by Spanish journalist Alfonso Sánchez. The denomination for these films in Italy is western all'italiana (Italian-style Western). Italo-Western is also used, especially in Germany. In addition, the term Paella Western has been used for the many Western films produced in Spain. The term Eurowesterns may be used to also include Western movies that were produced in Europe but not called Spaghetti Westerns, like the West German Winnetou films or Ostern Westerns. The majority of the films were international co-productions between Italy and Spain, and sometimes France, West Germany, Portugal, Greece, Israel, Yugoslavia, or the United States.