It seems there might be a misunderstanding. The current Pope is Pope Leo XIV, and here's some information about the legacy of Pope Leo XIII, who reigned from 1878 to 1903.

Pope Leo XIII and Rerum Novarum

Pope Leo XIII is most well-known for his encyclical Rerum Novarum (1891), which addressed the rights and conditions of workers amidst industrialization 1.

• Social Justice: Rerum Novarum laid the groundwork for Catholic social teaching by advocating for workers' rights, the dignity of labor, and social justice, while also upholding the importance of private property 1.
• Engagement with the Modern World: Leo XIII aimed to reconcile faith and reason, promoting education, dialogue, and better relations with other Christian denominations. His papacy marked a move towards a more progressive Church, encouraging Catholics to actively participate in social and political life 1.
• Impact and Influence: Rerum Novarum became a foundational document for Christian social action, offering principles rooted in Revelation, natural law, and morality to evaluate and transform socio-political systems 2 3. It addressed the distress of industrial laborers and outlined Catholic teachings on work, property rights, collaboration, and the dignity of the poor 3.
• The Church's Role: Leo XIII emphasized the Church's role in social matters, asserting the right to defend workers' rights and stating that no solution to social questions could be found without the Church's counsel 4. He believed that serious social problems could only be solved through cooperation, with the Church playing an active part 5.

Other Key Contributions

Beyond Rerum Novarum, Leo XIII made significant contributions to the Church and society:

• Revival of Thomism: He strongly encouraged the renewal of philosophical and theological studies, particularly through his encyclical Aeterni Patris, which promoted the study of St. Thomas Aquinas and contributed to the development of Neothomism 6 7.
• Marian Devotion: Leo XIII had a deep Marian devotion and promoted traditional forms of popular piety, especially the Rosary. He recommended the Rosary as a spiritual tool to combat societal evils 6.
• Diplomatic Efforts: He strengthened the Vatican's diplomatic relations with various countries, enhancing the Church's global influence 1.
• Response to Social Issues: Leo XIII addressed the social question by applying traditional doctrines to modern conditions, refuting socialist theories, and advocating for the combined action of the Church, the State, employers, and employees 8.
• Guidance for Christian Citizens: He provided guidance on the duties of Christian citizens and the importance of unity in faith for preserving the moral foundations of the State 7 9.

In summary, Pope Leo XIII's papacy is remembered for his landmark encyclical Rerum Novarum, his efforts to engage the Church with the modern world, his promotion of Thomistic philosophy, and his Marian devotion. His work laid the foundation for modern Catholic social teaching and continues to influence the Church's approach to social justice and human dignity.