[5] During his one-year stay in the United States, he joined the Cuban Revolutionary Committee and became the editor of a journal called La Revolución.

Hostos believed in the creation of an Antillian Confederation (Confederación Antillana) between Puerto Rico, the Dominican Republic and Cuba.

One of the things which disappointed Hostos was that in Puerto Rico and in Cuba there were many people who wanted their independence from Spain, but did not embrace the idea of becoming revolutionaries, preferring to be annexed by the United States.

[5] He spent one year in Lima, Peru, from November 1870 to December 1871,[6] during which he helped develop the country's educational system and spoke against the harsh treatment given to the Chinese who lived there.

In April 1876, Hostos returned to New York and in November he traveled to Caracas, Venezuela, where he married Belinda Otilia de Ayala Quintana (1862–1917), from Cuba, on July 9, 1877.

He wrote many essays on social science topics, such as psychology, logic, literature and law, and is considered one of the first systematic sociologists in Latin America.

Hostos wrote his own epitaph:[5] "I wish that they will say: In that island (Puerto Rico) a man was born who loved truth, desired justice, and worked for the good of men."

In Puerto Rico there are multiple monuments dedicated to Hostos: The Municipality of Mayagüez has inaugurated a cultural center and museum near his birthplace in Río Cañas Arriba ward.

The city of Mayagüez also has named in his honor: The Miguel Cervantes Virtual Library of Spain has dedicated a portal on its website to Eugenio María de Hostos.

[34] Their son Juan José de Ostos y del Castillo was born in Camagüey in 1750 and moved to Santo Domingo, Dominican Republic.

[35] Sometime after France seized control of the entire island of Hispaniola in 1795, Juan José changed the spelling of his surname to Hostos.

[35] Before his death in 1816, Juan José had four children with María, the second of which was Eugenio de Hostos y Rodríguez, born in 1807, who later became Secretary to Isabella II of Spain.