The Secretariat of State is a body of the Roman Curia that is closely linked to the heart of the papacy, insofar as it operates in direct union with the pope and makes his wishes a reality. Studying its development is helpful for identifying the evolution of the policies of the popes and, above all, the evolution of the institution of the papacy. The more the papacy assumes a central role in Catholicism, the more it requires effective political offices. Thus, the Secretariat of State constitutes that key uniting feature between the will of the pope and the structure of the Roman government, local churches, and national governments. The history of the Secretariat of State is an institutional history and a history of its members; it is a history that can be properly understood from the perspective of religious history; it is a history of the ideas and power within the Church.

The chapter addresses the history of the Synod of Bishops, created by pope Paul VI in September 1965 and reformed by Francis I between 2018 and 2023, with an analysis of the different phases: from the proposals emerging from the bishops during the Second Vatican Council (1962–65), to the Synods’ assemblies of Paul VI (r. 1963–78), John Paul II (r. 1978–2005), and Benedict XVI (r. 2005–13). After half a century of its life, the Synod of Bishops has changed, especially during pope Francis I’s pontificate, from an expression of episcopal collegiality (representing the bishops only), useful as a device of papal primacy, to an institution of ecclesial synodality, giving voice to all kinds of members in the Catholic Church, including women and lay people.

The chapter deals with the central provisions of the two Latin codifications on the papal office, each in the context of the structure of the Code (norms on the supreme authority of the Church; position of the pope in the College of Bishops; legal qualification of papal authority, acquisition and loss of authority). In doing so, it is shown that the current Codex Iuris Canonici has essentially confirmed the concept of papal primacy that already distinguished the Code of 1917. Nevertheless, the question is then explored whether, according to the legal order of the Church, substantial developments or even modifications of the papal primacy, or at least its exercise, are possible. For this purpose, some perspectives are presented.

Canon law has played a role in the life of the Church since its earliest days. For many centuries, it was largely customary and local. However, from the sixth century on, the Roman pontiff played an increasingly prominent role in shaping and applying this law in the West. This tendency to centralize authority in the hands of the Roman pontiff reached its culmination with the promulgation of the first Code of Canon Law in 1917. Cut off from the law’s roots in history and theology, this code derived its force from the will of the pontiff who enacted it. The Second Vatican Council, from 1962 to 1965, attempted to balance the role of the pope with that of the College of Bishops and to move toward decentralization of authority by enhancing the figure of the diocesan bishop and creating episcopal conferences. These conciliar efforts have been implemented, at least in part, in the revised Latin code of 1983 and the Code of Canons of the Eastern Churches of 1990. Nevertheless, subsequent legislating has come largely through the unilateral action of the Roman pontiff.