The see of Osma was restored in 1101, and a new town, the Burgo, grew round the cathedral on the Ucero, across the river from the old royal town of Osma.
The Burgo is the bishop's own lordship, raised to a villa by a privilege of Alfonso VIII, while Osma itself stays royal. It is a small lordship, but its chapter is the most reformed in Castile and the cradle of the future Dominicans.
Who holds it
- Name
- Martín Bazán
- Title
- Bishop of Osma
- Since
- 1190
- Confidence
- medium
Bishop until his death in 1201. A reformer: under him the cathedral chapter lives as canons regular under the rule of Saint Augustine, with Diego de Acebes as prior and the young Dominic of Caleruega among the canons. Diego succeeds him as bishop in 1201.
What it holds
- El Burgo de Osma: the episcopal town round the cathedral, held by the bishop
- Not held: Osma (Uxama) across the Ucero, a royal town with its castle
How it was acquired
Bishop Pedro de Bourges (1101-1109) rebuilt the see beside the river; the Burgo grew round the cathedral and received villa status from Alfonso VIII (date not pinned).
How things stand that morning
Held by the bishop.
Wealth
Market and rents of the Burgo; tithes of the diocese along the upper Duero; pilgrims and travellers on the Duero road.
Threats
- Friction with the royal town of Osma
Advocates and rivals
The royal town of Osma and its council across the river; the Castilian crown.
Places of note
- Cathedral of El Burgo de Osma: Seat of the bishop and of the reformed chapter of canons regular
Where the sources disagree
Evidence: The episcopal character of the Burgo is clear; the date and wording of the royal privilege and the extent of the lordship are not pinned.
On the map: A disc round the Burgo, because the modern municipality joins it with royal Osma.
Primary sources for Castile
Chronicles, registers, sagas and inscriptions written in or near 1200 that cover this entry. Each has its own page with editions, translations and where to read it.
- Annals of Toledo and other short Iberian annals (12th and 13th centuries; Anales Toledanos I to 1219). Florez's volume 23 gathers the short annals of the peninsula. Read online
- Chronicle of the World (Lucas of Tuy), Lucas de Tuy (1236, for Queen Berenguela). The Leonese counterpart to Rodrigo, written at San Isidoro for Berenguela. Read online
- Latin Chronicle of the Kings of Castile, Anonymous, probably Juan of Osma, chancellor of Castile (about 1223 to 1239). The chancellor's chronicle of Alfonso VIII's reign, detailed from the 1190s. Read online
- Chronicle of Roger of Howden, Roger of Howden (about 1192 to 1201). The fullest single narrative for the year. Read online
- The Complete History: the passages on the Maghreb and al-Andalus, Ibn al-Athir (about 1220 to 1231, at Mosul). The year entries for 595 to 597 of the Hijra (late 1198 to 1201) record the death of Yaqub al-Mansur, the accession of al-Nasir and the opening of Yahya ibn Ghaniya's war in Ifriqiya; the following years follow Yahya and the Ghuzz captain Qaraqush through Tripoli, Gabès and Mahdia to al-Nasir's reconquest in 1206, with the best eastern account of Qaraqush's career. Read online
- The Garden of Pages: a History of the Kings of the Maghreb and of the City of Fez, Ibn Abi Zar al-Fasi (completed in 1326 at Fez, for the Marinid sultan Abu Said Uthman). The Almohad chapters give a brisk dated narrative of al-Mansur's death and burial, al-Nasir's accession and the Banu Ghaniya troubles, with the kind of detail (coinage, public works at Fez and Rabat, prices, plagues) that a Fez compiler cared about, and the annals of Fez supply the city's governors and markets. Read online
- The Wondrous Account of the History of al-Andalus and the Maghreb, Ibn Idhari al-Marrakushi (about 1312, at Marrakesh). The Almohad section is the fullest year-by-year narrative of the caliphate around 1200: the last campaigns and the death of Abu Yusuf Yaqub al-Mansur in January 1199, the accession of his son Muhammad al-Nasir, the renewed war of the Banu Ghaniya in Ifriqiya under Yahya ibn Ishaq and his ally Qaraqush, the Almohad losses of Mahdia and Tunis a few years later, and al-Nasir's reconquest of Ifriqiya in 1205 to 1206 followed by the appointment of Abd al-Wahid ibn Abi Hafs as governor. Read online
- Deeds of Philip Augustus, Rigord (about 1186 to 1206, in stages). The French court's own chronicle for the year, from the monk of Saint-Denis who called himself the king's chronographer. Read online
13 more in the sources library for France and Iberia.
Sources and studies
Last revised 4 November 2026. Published 4 November 2026. Suggest a correction on the OMNIA Discord.