Even before the Bohemian reform movement known as Hussitism was condemned at the council of Constance, the Hussite teachings became subject of intensive religious polemics. From the first decade through the end of the fifteenth century, more than 250 polemical treatises contra Hussitas were produced. Due to the dynamics of the development in Bohemia, the Church authorities failed to eradicate the Hussite heresy by means of inquisition. The repression of Hussitism included two waves of crusades in 1420-31 and 1467-71, as well as a number of executions of Hussite sympathizers outside the Kingdom of Bohemia. The extermination efforts were interrupted by attempts at a reduction of the heretics by way of disputation, famously at the Council of Basel in 1433-37.