The 21 Ecumenical Councils of the Church
Share1 First Council of Nicaea (325 AD) – Formulated the Nicene Creed and declared Christ's true divinity against Arianism.
2 First Council of Constantinople (381 AD) – Expanded the Nicene Creed and affirmed the divinity of the Holy Spirit.
3 Council of Ephesus (431 AD) – Defined Mary as the Theotokos (Mother of God) and rejected Nestorianism.
4 Council of Chalcedon (451 AD) – Defined that Christ has two distinct natures (divine and human) united in one person.
5 Second Council of Constantinople (553 AD) – Reaffirmed previous Christological decrees and condemned certain writings.
6 Third Council of Constantinople (680–681 AD) – Declared that Christ has both a human and a divine will against monothelitism.
7 Second Council of Nicaea (787 AD) – Defended the use and veneration of sacred images (icons) against iconoclasm.
8 Fourth Council of Constantinople (869–870 AD) – Addressed the Photian schism and matters of church discipline.
9 First Lateran Council (1123 AD) – Addressed the rights of the Church and the investiture controversy in the West.
10 Second Lateran Council (1139 AD) – Worked on church reform and healed a schism.
11 Third Lateran Council (1179 AD) – Regulated papal elections and condemned the Albigensian heresy.
12 Fourth Lateran Council (1215 AD) – Defined the doctrine of transubstantiation and mandated annual confession and communion.
13 First Council of Lyons (1245 AD) – Deposed and excommunicated Emperor Frederick II.
14 Second Council of Lyons (1274 AD) – Attempted a brief reunion with the Eastern Church and regulated the papal conclave.
15 Council of Vienne (1311–1312 AD) – Suppressed the Knights Templar and addressed church reform.
16 Council of Constance (1414–1418 AD) – Ended the Western Schism and condemned Jan Hus.
17 Council of Basel-Ferrara-Florence (1431–1445 AD) – Attempted reunion with various Eastern Christian churches.
18 Fifth Lateran Council (1512–1517 AD) – Addressed church discipline and reform just prior to the Reformation.
19 Council of Trent (1545–1563 AD) – Responded to the Protestant Reformation, clarified doctrine, and reformed the clergy.
20 First Vatican Council (1869–1870 AD) – Defined papal infallibility and the relationship between faith and reason.
21 Second Vatican Council (1962–1965 AD) – Addressed the role of the Church in the modern world and renewed the liturgy