The Conclave was, next to the Supreme Council of sorcerers, one of the two main bodies ruling the magicians. The most powerful sorcerers of their times sat on it. One of it's duties was regulating the standards and rules of using magic - the ban on necromancy was one of it's edicts. Before the Thanedd rebellion, a large part of the Conclave conspired with Nilfgaard. During those events most of it's members died, the sole survivor being Francesca Findabair. After the coup the Conclave was not reactivated, thus many mages do not respect the restrictions it had created.