Developing doctrine : Nicaea I (325) to Constantinople III (680-681)
Prayer and politics : Nicaea II (787) and Constantinople IV (869-870)
Supervising the early church : disciplinary canons
Four Lateran councils : 1123-1215
Power struggles : Lyons I (1245) to Vienne (1311-1312)
Supervising the medieval church : disciplinary canons
Councils vs. popes : Constance (1414-1418) and Basel-Ferrara-Florence-Rome (1431-1445)
Reform lost and regained : Lateran V (1512-1517) and Trent (1545-1563)
Papal infallibility : Vatican I (1869-1870)
Brave new world, brave new council : Vatican II (1962-1965).
