The Spiritism was introduced in Puerto Rico during the second half of the 19th century. At that time Puerto Rico was a colony of Spain, and the official religion was Catholicism. The political environment was characterised by repression of civil rights. However, a number of middle-class Puerto Ricans had the opportunity to go to Europe to study and were influenced by the books of a French educator and philosopher who wrote under the pseudonym Allan Kardec (1804-1869). Kardec is considered the father of Spiritism because he was responsible for compiling the spiritism doctrine in a series of books. Upon the return of this group of Puerto Rican intellectuals, the spiritism ideal began to spread on the island.

The Spiritism works such as the Spirits‘ Book and the Mediums’ Book became very popular among the Puerto Rican intellectual community basically because they preached the ideal of equality and social justice. Some Puerto Rican leaders such as Rosendo Matienzo Cintrón and Manuel Corchado y Juarbe became interested in spiritist philosophy and made references to spiritism doctrine in their speeches to the Puerto Rican community.

At first, spiritism groups had to organise themselves secretly because the Spanish government thought they were affiliated with revolutionary groups. Because of this, some spiritism was persecuted and arrested by the Spanish government. The country's newspapers published articles in which spiritism was described as "an abominable social cancer" and a cause of mental illness. In 1875 the Boletín Mercantil, a government newspaper, reported that spiritism was ‘invading’ the island. Spiritism was denied sacraments such as baptism and marriage.

Despite the repression, the spiritism movement grew rapidly and several spiritism centres were organised in different parts of the island. The first spiritism centre was founded in 1881 in the town of Mayagüez, and was called Renacimiento. During the last two decades of the 19th century, spiritism groups promoted reforms in the areas of education, health and politics. As part of these reforms, they organised libraries and published a significant number of newspapers. Spiritist leaders considered the study of Spiritism essential for the intellectual and moral growth of the Puerto Rican community. In 1873 Manuel Corchado y Juarbe presented a bill in the Spanish Cortes recommending that spiritism be studied in secondary schools.

The Spiritism groups also worked to improve health services by creating several hospitals around the island. They were involved in the struggle for social and political reforms. For example, in 1888 a group of spiritists sent delegates to the First Congress of Spiritists held in Barcelona to condemn the abuse and repression of the Spanish government. Spiritism leaders such as Matienzo Cintrón and Emeterio Bacon were also prominent politicians who were committed to achieving greater freedom and justice for Puerto Ricans.

In 1898, the United States invaded Puerto Rico and took possession of the island. This event occurred six months after Spain had granted autonomous government to the island. Under U.S. rule, Puerto Rico once again became an oppressed colony.

Spiritism continued to grow on the island, and in 1903 a group of spiritists founded the "Federación de Espiritistas de Puerto Rico" (Federation of Spiritism of Puerto Rico). This organisation was dedicated to promulgating spiritism and promoting the cohesion of spiritist centres. The Federation began to organise annual conventions in which spiritists gave conferences and discussed the development of Spiritism on the island.

In 1913, a dentist named Francisco Ponte became the president of the Federation. Ponte is considered the first Puerto Rican parapsychologist. He conducted several experiments with a medium and reported them to the American Society for Psychical Research.

By 1923, Ponte wrote that there were about 150 spiritism centres on the island that were incorporated into the Federation. However, a few years later the Federation began to experience an administrative crisis due to a lack of leadership and the indifference of the spiritism centres to the payment of dues. The Federation's crisis was also brought about by disagreements among its leaders regarding the conception of spiritism as a science or as a religion. For example, according to spiritist leaders such as Telesforo Andino, spiritism should be conceived as the religion of science. Andino believed that religion had a positive function in the development of humanity. On the other hand, William Colón believed that to consider Spiritism as a religious doctrine was against its scientific character. For Columbus, religion is the greatest enemy of humanity.

The Spiritism in Puerto Rico began as a middle-class movement led by intellectual and academically oriented Puerto Ricans. They became interested in Spiritism attracted by a philosophical system that provided a doctrine oriented to the social and moral development of the individual. However, there was another group of Puerto Ricans, generally from the poorer classes, who became interested in spiritism for different reasons. The Puerto Rican poor found Spiritism to address issues pertinent to their lives such as the value of suffering with resignation. Kardec emphasised in his books that in life there are trials that one must pass with resignation in order to achieve moral perfection. This idea was very attractive to a large number of Puerto Ricans who were trying to find meaning in Spain's oppressive regime.

Another element that promoted the acceptance of Spiritism among the Puerto Rican poor was its Christian orientation. Kardec always stressed that there was no conflict between the Bible and spiritism philosophy. Moreover, he wrote a book on how the Bible agrees with spiritism principles such as reincarnation and communication with spirits (The Gospel According to Spiritism). Related to this we have to consider that Kardec never considered Spiritism as a religion, which resulted in Puerto Ricans experiencing no dissonance in being both spiritism and Catholicism. They did not have to stop being Catholic to become spiritists. The fact that the Catholic Church accepts that it is possible to communicate with guardian angels and saints facilitated the legitimisation of spiritism among Puerto Rican Catholics.

Finally, one of the major factors contributing to the popularity of Spiritism among the poor was its emphasis on the reality of the spiritual world and the need to sacrifice satisfaction and pleasure in order to keep focused on spiritual goals.

All the factors mentioned above can help us to explain why Spiritism, instead of remaining a middle class movement, began to be practised by the unprivileged Puerto Rican community to solve their health problems. This group of Puerto Ricans began to practice a Spiritism that was not the one preached by Kardec in his books, but integrated elements of the folkloric medicine known to them into Spiritism. That is to say, they syncretised Spiritism with ideas of popular Catholicism, quackery, plant medicine and other popular healing practices. This spiritism practice is, in a way, a socio-cultural creation that integrates diverse religious and cultural traditions.