What was a lay investiture?

Lay investiture was a practice in medieval Europe where secular rulers, such as kings or nobles, appointed bishops and other church officials, often granting them symbols of their office. This led to significant conflict between the church and state, particularly during the Investiture Controversy in the 11th and 12th centuries, as church leaders sought to maintain spiritual authority and independence from secular influence. The controversy ultimately resulted in reforms that clarified the roles of church and state in appointing religious leaders.