After coming to power, King Alfonso IX, faced an attack by his two neighbours, Castile and Portugal, decided to summon the Curia regis. This was a mediæval organisation composed of aristocrats and bishops, but because of the seriousness of the situation and the need to maximise political support, Alfonso IX took the decision to also call the representatives of the urban middle class from the most important cities of the kingdom to the assembly.
However, all these meetings were exceptional and did not lead to a regular attendance of town representatives in the Curiae.
León's Cortes dealt with matters like the right to private property, the inviolability of domicile, the right to appeal to justice opposite the King and the obligation of the King to consult the Cortes before entering a war.
Despite what is believed, the Icelandic Althing in 930, sometimes taken as a previous example concerning legislative assemblies, was an exclusive meeting of magnates and did not produce legislative texts until the thirteenth century. In addition, it was similar to the Palatinate of the VIII century of the kingdom of the Astures and inferior to the Royal Curies that were celebrated from year 830 in the Court of Oviedo, in which they were represented nobles and ecclesiastics so Hispanics assemblies were politically more advanced. The Althing would be similar, in addition to the Asturian Palatinate, to the Visigothic Councils of the sixth century, also earlier, composed only by a social arm of powerful people; that in this ecclesiastical case was in order to legislate matters such as the Fuero Juzgo.