Juan Nepomuceno Guerra Cárdenas (July 18, 1915 – July 12, 2001) was a Mexican crime lord, bootlegger, businessman and smuggler who founded the Gulf Cartel, a drug trafficking organization. He is often considered the "godfather" of U.S-Mexico border cartels.
He began his criminal career in the 1930s by smuggling alcohol from Mexico during the Prohibition in the United States. He later diversified to other cross-border smuggling activities. He is the uncle of Juan García Ábrego, once's Mexico's most-wanted man.
During the 1930s he began smuggling whisky across the Mexico-United States border through south Texas. Through shrewd political connections he had fostered, Nepomuceno Guerra was able to control all the contraband moving across the Rio Grande.  In the 1970s, his nephew Juan García Abrego began utilizing those connections and developed the organization into a drug cartel primarily dedicated to the more lucrative business of smuggling cocaine.
According to news sources, despite allegedly founding one of the largest drug cartels in Mexico, Juan Nepomuceno Guerra never spent more than "a few hours in jail" for his crimes.
He died of respiratory disease.
On June 18, 2015, the Governor of Tamaulipas Egidio Torre Cantú inaugurated a street under his name, "Juan N. Guerra", in Reynosa, Tamaulipas.The street was inaugurated along with seven others and is located in the working-class neighborhood Reserva Territorial Campestre.