In July 1138 Rodrigo died at the
Siege of Coria and the king immediately appointed Osorio
count (
comes) in his place and granted his
tenencias of León,
Aguilar,
Campos, and perhaps
Zamora. Osorio and his brother's erstwhile vassals carried Rodrigo's body to the city of León for burial in the family mausoleum beside his parents. There they buried him in a church next to the
Cathedral of Santa María, possibly the monastery of
San Pedro de los Huertos, which his parents had received by a royal grant of
Urraca of Zamora and
Elvira of Toro in 1099. Osorio held numerous property interests in the city of León. Osorio's succession to his brother and the burial of Rodrigo are recorded in the
Chronica Adefonsi: Alfonso gathered all of his advisors, and in their presence, he appointed Osorio, Rodrigo's brother, to be consul in his place. . . . Count Osorio, the new consul, took the body of his brother to León. He was accompanied by his own military force and by that of his brother. The mourning over the death of Rodrigo Martínez increased in every city. In León they buried him with honors in his father's tomb near the Basilica of Saint Mary. The tomb is located very near the episcopal throne. Sometime before 28 January 1141, Osorio married Teresa, daughter of
Fernando Fernández de Carrión and Elvira, a daughter of
Alfonso VI of León. They had five daughters and three sons: Aldonza, Constanza, Elvira, Fernando, Gonzalo, Jimena (second wife of
Rodrigo Gutiérrez Girón), Rodrigo, and Sancha. (Calderón Medina and Ferreira suggest an additional child, Portuguese nobleman Monio Osores of Cabreira and Ribeira.) From January 1139 to the summer of 1141 Osorio was regularly at court. On 22 February 1140 he was at
Carrión de los Condes to witness the treaty between Alfonso VII and
Raymond Berengar IV of Barcelona. But in the summer of 1141 he fell from favour and his
tenencias were confiscated (Melgar, Malgrat, Mayorga, Liébana, León, Aguilar, Campos, Zamora). Among the few
tenencias he was left with were
Peñafiel (1146),
Villafrechós (1147–59),
Villalobos (1147–59),
Becilla de Valderaduey (1151–57),
Cotanes (1155), and
Arales (1157). After June 1142 Osorio rarely visited the royal court. In May 1146 he visited the court of
Alfonso I of Portugal, perhaps as an exile. ==Later life (1147–1160)==