Council of Trent (1545–1563): The Catholic Counter-Reformation

The Council of Trent was the Catholic Church’s response to the Protestant Reformation, meeting in three periods between 13 December 1545 and 4 December 1563, mainly in the city of Trent (Trento) in northern Italy. Its decrees defined Catholic teaching on Scripture, salvation and the sacraments, and ordered sweeping reforms of bishops and clergy. Together with the new religious orders and the reforming popes who followed, it shaped Catholicism, often called “Tridentine” after the council, until the Second Vatican Council of the 1960s.

Background: a Church divided

By the 1520s the movement begun by Martin Luther’s 95 Theses had split the Church in much of Germany and Switzerland. Luther and others appealed for a free general council, and many Catholics agreed that only a council could settle disputed doctrine and correct well-known abuses, such as absentee bishops, poorly educated priests and the sale of church offices.

Popes hesitated. Memories of the 15th-century councils of Constance and Basel, which had claimed authority over the papacy, made Rome wary. Wars between Emperor Charles V and King Francis I of France also made it hard to agree on time and place. Paul III, elected in 1534, summoned councils to Mantua (1537) and Vicenza (1538), but neither met.

Charles V wanted a council on German soil that might reconcile the Protestants. The papacy preferred Italy. Trent, an Italian-speaking city that was nonetheless part of the Holy Roman Empire, was the compromise. Paul III convened the council there with the bull Laetare Hierusalem in 1544.

The council in three periods

The council did not sit continuously. It met in three separate periods under three different popes, interrupted by war, epidemics and quarrels between Rome and the Catholic monarchs. Voting was by individual bishops and the heads of some religious orders, rather than by nation as at Constance, which gave the many Italian bishops a strong voice.

Much of the detailed work was done in congregations, working meetings where theologians debated draft texts before the bishops voted on them. The decrees were then read out and approved in formal public sessions. Each doctrinal decree usually came in two parts: a positive statement of Catholic teaching and a list of canons condemning opposing views, each ending with the formula “let him be anathema”.

The first period, 1545–1549

The council opened on 13 December 1545 with only about 30 bishops present, most of them Italian. It was led by three papal legates: Giovanni Maria del Monte (later Pope Julius III), Marcello Cervini (later Marcellus II) and the English cardinal Reginald Pole. An early decision to treat doctrine and reform side by side satisfied both the papacy and the emperor.

The first period produced several of the council’s most important decrees:

• Scripture and tradition (April 1546). Revelation was handed down both in Scripture and in unwritten traditions; the council fixed the canon of the Bible, including the books Protestants called the Apocrypha, and declared the Latin Vulgate authentic for teaching.
• Original sin (June 1546). Baptism removes the guilt of original sin.
• Justification (January 1547). The long decree on how sinners are made right with God rejected the Protestant teaching of justification by faith alone, holding that grace is given freely but that people cooperate with it and that good works matter.
• The sacraments (March 1547). There are seven sacraments, which confer grace.

In March 1547 fear of an epidemic led most fathers to move to Bologna. Bishops loyal to Charles V stayed in Trent, and the angry emperor refused to recognise the move. Work stalled, and Paul III suspended the council in 1549, shortly before his death.

The second period, 1551–1552

Julius III reopened the council at Trent in May 1551. It issued decrees on the Eucharist, affirming the real presence of Christ and the doctrine of transubstantiation (October 1551), and on penance and the anointing of the sick.

Envoys from several German Protestant states arrived in late 1551 and early 1552. They demanded that earlier decrees be reopened and that the council be declared superior to the pope, conditions the fathers would not accept. In spring 1552 the Protestant prince Maurice of Saxony turned against the emperor and his troops advanced towards the Tyrol. The council was suspended in April 1552.

The following decade was hostile to councils. Pope Paul IV (1555–1559) preferred to reform the Church directly from Rome, and the Peace of Augsburg of 1555 accepted Lutheranism as a legal religion in the Empire.

The third period, 1562–1563

Pius IV reconvened the council in January 1562, now facing a Protestantism that had spread to France, Scotland and the Netherlands. This period was the largest and the most contentious. Spanish and French bishops pressed for a declaration that bishops’ duty to reside in their dioceses was of divine law, which papal supporters feared would weaken Rome’s authority.

The deadlock almost broke the council in early 1563. Cardinal Giovanni Morone, appointed chief legate that spring, negotiated directly with Emperor Ferdinand I and other rulers and steered the fathers to compromise. In its final months the council passed decrees on:

• The Mass as a sacrifice and on communion under one kind (1562).
• Holy orders, including the decree requiring every diocese to set up a seminary to train priests (July 1563).
• Marriage, including the decree Tametsi, which made marriages valid only if celebrated before a priest and two witnesses (November 1563).
• Purgatory, the saints, sacred images and indulgences (December 1563), affirming these practices while condemning superstition and financial abuses.

Reform decrees required bishops to live in their dioceses, preach, visit parishes and hold synods, and limited the holding of several church offices at once. The council closed on 4 December 1563; around 255 fathers signed its decrees. Pius IV confirmed them in the bull Benedictus Deus, dated 26 January 1564.

Key people

• Paul III (pope 1534–1549) convened the council after years of delay.
• Charles V (emperor 1519–1556) pushed for a council to heal the German schism and clashed with Rome over its location and aims.
• Reginald Pole, Marcello Cervini and Giovanni Maria del Monte led the first period as papal legates.
• Pius IV (pope 1559–1565) reopened and concluded the council.
• Giovanni Morone rescued the final period through diplomacy in 1563.
• Charles Borromeo, Pius IV’s nephew and later Archbishop of Milan, coordinated work in Rome and became the model reforming bishop.

Implementation and consequences

The council asked the pope to complete several tasks it could not finish. Rome issued an Index of Prohibited Books (1564), the Roman Catechism (1566), a revised Breviary (1568) and the Roman Missal (1570). The Missal standardised the Latin Mass that later became known as the Tridentine Mass. A revised official Vulgate followed in 1592.

Putting the decrees into practice took generations and varied by country. Philip II of Spain accepted them quickly, though with reservations about royal rights, while France never formally received the reform decrees as law. Bishops such as Borromeo in Milan, and new orders such as the Jesuits, spread seminaries, catechism teaching and regular preaching across Catholic Europe and its overseas missions.

The council’s influence reached well beyond theology. Its brief decree on sacred images, which asked that art should teach the faith clearly and avoid anything disorderly or indecent, encouraged churchmen to supervise religious painting more closely. Historians often link this climate to the dramatic, accessible religious art of the Baroque. Seminary training gradually produced a better-educated parish clergy, and the Tametsi decree changed how Catholic marriages were contracted for centuries.

The council did not reunite Christianity. By defining doctrine sharply against Protestant positions, it confirmed the division between Catholic and Protestant churches that the wars of religion would soon harden.

Myths and facts

• Myth: Trent was the start of Catholic reform. Reform movements were already active before 1545, including new orders such as the Theatines, Capuchins and Jesuits. Historians today often speak of both a Catholic Reformation and a Counter-Reformation.
• Myth: the council nearly banned polyphonic church music until Palestrina saved it. The story that Palestrina’s Missa Papae Marcelli persuaded the council not to ban polyphony is a later legend. The council’s decree on music was brief and general, warning against anything “lascivious or impure”.
• Fact: attendance was small. Even at its largest the council drew only around 200–270 voting fathers, the great majority Italian, out of several hundred Catholic bishops worldwide.

By the numbers

Timeline

• 1544, November: Paul III summons the council to Trent.
• 1545, 13 December: The council opens at Trent.
• 1546, 8 April: Decree on Scripture and tradition.
• 1547, 13 January: Decree on justification.
• 1547, March: Most fathers move to Bologna.
• 1551, 1 May: Julius III reopens the council at Trent.
• 1552, 28 April: The council is suspended as war approaches.
• 1562, 18 January: Pius IV reopens the council.
• 1563, 4 December: The council closes after its 25th session.
• 1564, 26 January: Pius IV confirms the decrees.

Why it matters

The Council of Trent gave the Catholic Church a clear, unified body of doctrine and a programme for training and disciplining clergy. For roughly 400 years, Catholic worship, catechism teaching and the priesthood were shaped by its decisions. It also fixed the doctrinal lines that separated Catholics from Protestants, a division that defined European religious and political life for centuries.