High Quality Content by WIKIPEDIA articles! The Investiture Controversy or Investiture Contest was the most significant conflict between Church and state in medieval Europe. In the 11th and 12th centuries, a series of Popes challenged the authority of European monarchies over control of appointments, or investitures, of church officials such as bishops and abbots. Although the principal conflict began in 1075 between Pope Gregory VII and Henry IV, Holy Roman Emperor, a brief but significant struggle over investiture also occurred between Henry I of England and Pope Paschal II in the years 1103 to 1107, and the issue played a minor role in the struggles between church and state in France as well. The entire controversy was finally resolved by the Concordat of Worms in 1122.