As Minister of Public Works in a conservative Catholic government (1873-1878), Beernaert improved the country’s rail, canal and road transport system. He founded new harbours in Ostend and Antwerp. In 1888, he became Prime Minister. He also served as a minister for finance for 10 years. During his term, social and legal reforms were introduced to improve the living conditions of workers, a line of fortifications was constructed along the Meuse to protect Belgium’s neutrality, and the right to vote was granted to ten times as many Belgian citizens as previously. By his work and attitude, he was living proof of the correctness of his own aphorism: “the primary virtue of politics and the basis for success is perseverance”.

He was involved in international efforts to abolish slavery. He opposed the exploitation of people in the Congo, which affected his relations with King Leopold. After he resigned as Prime Minister, he was an active member of the Inter-Parliamentary Union. At the Hague Peace Conference in 1899, he headed the commission for the limitation of armaments. In 1907, he headed the second commission for codifications regarding war on land. As a member of the Permanent Court of Arbitration, he represented Mexico in its dispute with the US in 1902, the first case to be heard by the court. Later on, he appeared in many other cases. He initiated efforts aimed at the codification of maritime law. He served as president of the International Association of Lawyers (1903-1905). He died of pneumonia when returning home from a conference of the Inter-Parliamentary Union held in Geneva.

D’Estournelles de Constant embarked on his diplomatic career in 1876. He represented France in Bosnia, Turkey, the Netherlands, Great Britain and Tunis. He served as minister plenipotentiary. Repeatedly, he was a member of the French Parliament representing the radical socialist party.

From the time that he headed the French delegation to the Hague Peace Conference in 1899, he devoted himself almost exclusively to working for peace and arbitration. He was successful in persuading US President Theodore Roosevelt to submit the dispute with Mexico to the Permanent Court of Arbitration in The Hague, which allowed this court to commence its operations. In 1905, he established the Association for International Conciliation with branches abroad. He saw the establishment of a European union as a possible solution to Europe’s problems.

During World War I, he offered his château in the Loire Valley (Chateau de Clermont-Creans) to serve as a hospital for wounded soldiers. Together with Leon Bourgeois, he presented a plan for the foundation of the League of Nations. Later, he advocated inter-parliamentary cooperation, in particular between France and Germany.

Paul Henri D’Estournelles de Constant was a gifted writer and translator from ancient Greek. Among other things, he wrote a play based on the myth of Pygmalion and many articles on French politics, feminism, arbitration and aviation. He became a leading French authority on the United States. He was a member of an aristocratic family tracing its ancestry back to the Crusaders. An immensely energetic person, in addition to working as a diplomat and a politician, he still found time to engage in fencing, sailing and painting. He was fascinated with automobiles and airplanes which started coming into use during his lifetime.