La Solidaridad was an organization entirely composed of Filipino Ilustrados and exiled Liberals. It was established in Barcelona, Spain on December 31, 1888. The group was headed by Rizal's cousin, Galicano Apacible. The first newspaper issue was on February 15, 1889 with its editor being Graciano Jaena Lopez and transitioned to Marcelo H. Del Pilar in the passing years.

The reason why this was included in the Life and Works of Rizal because he was one of the core members of the group who goes by the pen name Dimasalang and Laong Laan. His articles were published from May 31, 1889 titled "La Verdad Para Todos" (The Truth for All) to his last article which was published on September 30, 1890 titled "Sobre la indolencia de los Filipinas" (On the Indolence of the Filipinos).

In total, Jose Rizal had written 10 articles for the La Solidaridad with the longest serialization being the "Filipinas Dentro de Cien Anos" (The Philippines within One Hundred Years), which had a total of 4 serialization. Its main topic is the prediction that the Philippines would eventually achieve independence, however the country would eventually fall in the American Colonization.