At least in the early Islamic era of the Umayyad the levy of Jizya was sufficiently onerous for non-Muslims and its revenue sufficiently significant for rulers that there were more than a few accounts of non-Muslims seeking to convert to avoid paying it and revenue conscious authorities denying them this opportunity. Robert Hoyland mentions repeated complaints by fiscal agents of revenues diminishing as conquered people converting to Islam, of peasants attempting to convert and join the military but being rounded up and sent back to the countryside to pay taxes, and governors circumventing the exemption on jizya for converts by requiring recitation of the Quran and circumcision.