County of Monzón

The County of Monzón was a marcher county of the Kingdom of León in the tenth and eleventh centuries, during a period of renewed external threat (the Caliphate of Córdoba) and disintegration of royal authority. The county was created by Ramiro II for Ansur Fernández in 943 and was ruled by his descendants, the Banu Ansúrez, for decades. The seat of the county was initially at the castle of Curiel and later at Monteson; to its east the river Pisuerga served as a border with the County of Castile. The County of Monzón straddled both banks of the Duero: south of the river its territories comprised Peñafiel or Sacramenia, north of the river it extended to the Cantabrian Mountains and included the populations of Redondos, Mudá, Rueda de Pisuerga, and Salinas de Pisuerga.

Ansur's successor as count was his son Fernando, who had five brothers. All five appear to have predeceased him and when he died he had no sons. His successor was his sister, Teresa Ansúrez, and, through her, her son, king Ramiro III of León. The king immediately travelled to Santa María de Fusiellos, the chief religious centre of the county, and endowed it with the villages of San Julián and Abandella in order to secure local support (and for the good of his soul). Fernando's widow, Toda, was allowed to retain the title cometissa (countess) and govern the city of Dueñas, which was part of Monzón.

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