Born in
Ybycuí, Caballero was a descendant of Spanish nobility, the son of Jose Ramón Caballero de Anazco (a descendant from
Túpac Huallpa through
Inca Garcilaso de la Vega) and his wife Melchora Inés Melgarejo y Genés. He married twice, to María de la Concepción Díaz de Bedoya and to Julia Álvarez. From the first marriage he had two children, Ramon Caballero de Bedoya, married to Martha Cahen, and had issue, and Melchora Caballero de Bedoya, married to her distant cousin Carlos Francisco Saguier Pereira. Outside of his marriages he had a further 90 children, all formally recognized by him, and thus today he has myriad descendants.
Military service Caballero joined the
Paraguayan Army in 1864 and fought in the
Paraguayan War. He participated in the
Mato Grosso campaign. Later he became the assistant of President
Francisco Solano López in
Humaitá and remaining loyal, rose through the ranks. He became an increasingly important leader of rearguard actions, eventually becoming a cavalry general. Caballero was the greatest living war hero, who was captured by Brazilians on 8 April 1870 near the
Apa River after the
Battle of Cerro Corá and released in May 1871. During his arrest he became friendly with Brazilians and their political and military support was instrumental later, during his political career. ==Post-war politics==