As a result of internal migration in Argentina since the 1960s, the veneration of San La Muerte has spread to Greater Buenos Aires and to the national prison system as well.

San La Muerte is one of many folk saints venerated in the Guaraní language region that covers parts of Paraguay, north-eastern Argentina and southern Brazil.

It is believed that San La Muerte was first venerated among the Guaraní Indians following the expulsion of their Jesuit missionaries in 1767, as a mixture of their previous beliefs and the newly imported Catholic faith.

The San La Muerte devotion involves prayers, rituals, and offerings, which are given directly to the saint in expectation of and tailored to the fulfillment of specific requests.

[citation needed] In addition to these powers, which are commonly attributed to folk saints in general, San La Muerte is also said to be able to grant a number of requests that are connected to crime and violence.

[citation needed] For most devotees San La Muerte offers personal and non-transferable protection that will only be accessible to others when – after the death of the original owner – he or she has acquired the sculpture.

There are also intermediaries such as brujos and traditional healers (curanderos) who invoke San La Muerte's power on behalf of their clients, usually concealing the image from sight of their customers.

Individual sculptures are addressed as San La Muerte (Because of the small size, such a statuette may be colloquially referred to as Santito, or 'Small Saint'.)

The representation of San La Muerte varies according to the individual sculptor that has crafted him, however, the classic image is a human skeleton, standing, with simple, minimalistic features.

[citation needed] San La Muerte sculptures can be carved from wood, bones, metal (especially bullets) and usually stand between 3 and 15 centimeters tall.

San La muerte tattoos, amulets and body insertions are believed to offer special protection from death, bodily harm and imprisonment.

[citation needed] Though San la Muerte is largely worshipped as a Catholic saint, it is important to note that he is not officially recognized by the church.