During the fourteenth and fifteenth centuries, the Portuguese Cortes had always been assemblies of the three estates, although the attendance of the nobility and clergy could vary, as could the number and representativeness of the participating municipalities. They were convened by the kings to debate various issues of great scope for the government of the kingdom, although the deliberations always belonged to the monarch. The Cortes of Coimbra in 1385 and Lisbon in 1439 have nevertheless different and unique characteristics. They were not convened by any monarch but by pressure from certain social forces in the kingdom. Some social bodies or powers did not want to be present. They took on deliberative functions and decided on matters never before attributed to the Cortes - in the first ones, the election of a king and in the latter, the choice of a regent. They were, therefore, essentially assemblies of the three estates, taking upon themselves the highest political power of deliberation, above the royal power. For all these reasons, these Cortes are presented as ‘irregular’ among all those that preceded and succeeded them, and they proofed of the political maturity of the Portuguese parliamentary system in medieval times.