of caballeros villanos, the "peasant knights" of Burgos, who provided the monarchs with a mounted contingent: in 1255 and 1266 royal charters granted to those citizens of Burgos who owned horses and could arm themselves relief from taxes, provided that they continue to live within the city walls. The merchant oligarchy succeeded the cathedral chapter as the major purchasers of land after 1250; they carried on their mercantile business in common with municipal or royal functions and sent their sons to England and Flanders to gain experience in overseas trade. A few families within the hermandades or confraternities like the Sarracín and Bonifaz succeeded in monopolising the post of alcalde, or mayor; a special court, the alcalde del rey was first mentioned at Burgos in 1281. By the reign of Alfonso X, the exemption of the non-noble knights and religious corporations, combined with exorbitant gifts and grants to monasteries and private individuals, placed great stress on the economic well-being of the realm.
In the century following the conquest of Seville (1248), Burgos became a testing ground for royal policies of increasing power against the consejo, in part by encouraging the right to appeal from the consejo to the king. In 1285, Sancho IV added a new body to the consejo which came to dominate it: the jurado in charge of collecting taxes and overseeing public works; the king reserved the right to select its members. The city perceived that danger to its autonomy came rather from an uncontrolled aristocracy during royal minorities: Burgos joined the hermandadesof cities that leagued together for mutual protection in 1295 and 1315. In the 14th century, official royal intrusion in city affairs was perceived as a palliative against outbreaks of violence by the large excluded class of smaller merchants and artisans, on whom the tax burden fell. Thealguacil was the royal official instituted to judge disagreements.
On 9 June 1345, sweeping aside the city
