Paul-Henri Charles Spaak (; 25 January 1899 – 31 July 1972) was an influential Belgian Socialist politician, diplomat, and statesman who thrice served as the prime minister of Belgium and later as the second secretary general of NATO. Nicknamed "Mr. Europe", he was a leader in the formation of the institutions that evolved into the current European Union, along with Robert Schuman, Alcide De Gasperi and Konrad Adenauer.

A member of the influential Spaak family, he served briefly in World War I before he was captured, and rose to prominence after the war as a tennis player and lawyer, becoming famous for his high-profile defence of an Italian student accused of attempting to assassinate Italy's crown prince in 1929. A convinced socialist, Spaak entered politics in 1932 for the Belgian Workers' Party (later the Belgian Socialist Party) and gained his first ministerial portfolio in the government of Paul Van Zeeland in 1935.

He became the prime minister in 1938 and held the position until 1939. During World War II, he served as foreign minister in the London-based Belgian government in exile under Hubert Pierlot, where he negotiated the foundation of the Benelux Customs Union with the governments of the Netherlands and Luxembourg. After the war, he twice regained the premiership, first for under a month in March 1946 and again between 1947 and 1949. He held various further Belgian ministerial portfolios until 1966. He was Belgium's foreign minister for 18 years between 1939 and 1966.

Spaak, a convinced supporter of multilateralism, became internationally famous for his support of international cooperation, in which he hoped to include geopolitical enemies of Belgium and NATO such as the Soviet Union and its satellite states. In 1945, he was chosen to chair the first session of the General Assembly of the new United Nations. A long-running supporter of European integration, Spaak had been an early advocate of customs union and had negotiated the Benelux agreement in 1944.

He served as the first President of the Consultative Assembly of the Council of Europe between 1949 and 1950 and became the first President of the Common Assembly of the European Coal and Steel Community (ECSC) — which would later become the European Parliament — between 1952 and 1954. In 1955, he was appointed to the so-called Spaak Committee studying the possibility of a common market within Europe and played an influential role in preparing the 1957 Treaty of Rome which established the European Economic Community (EEC). He received the Charlemagne Prize the same year. Between 1957 and 1961, he served as the second secretary general of NATO, becoming the only secretary general to have previously served as prime minister until Anders Fogh Rasmussen in 2009.

Retiring from Belgian politics in 1966, Spaak died in 1972. He remains an influential figure in European politics and his name is carried, among other things, by a charitable foundation, roads and structures, including one of the buildings of the European Parliament, and a method of negotiation.

Personal background and life Paul-Henri Spaak was born on 25 January 1899 in Schaerbeek, Belgium into the prominent Spaak-Janson family."Paul-Henri Spaak". Almanac of Famous People, 9th edition. Thomson Gale, 2007. His maternal grandfather, Paul Janson, was an important member of the Liberal Party. His mother, Marie Janson, was a socialist, and the first woman to enter the Belgian Senate, and his father, Paul Spaak, was a poet and playwright. Other noted members of his family included his uncle, Paul-Émile Janson, who served as Prime Minister of Belgium from 1937 to 1938, and his niece, Catherine Spaak, a movie star, singer and television presenter.

Paul-Henri Spaak and his wife Marguerite Malevez were married in 1921 and had three children: diplomat Fernand Spaak (1923–1981), Marie Marguerite Spaak (1926–2000, later married British diplomat Michael Palliser), and Antoinette Spaak (1928–2020), the first Belgian woman to lead a political party, the Democratic Front of Francophones. In 1943 Malevez was arrested by the Gestapo as a member of a resistance movement and imprisoned for a few weeks in Saint-Gilles Prison in Brussels. After his wife's death on 14 August 1964, he married 56-year-old Antwerp-born divorcee and longtime friend Simonne Rikkers Hottlet Dear (1908–1975) on 23 April 1965. His brother was the screenwriter Charles Spaak. One of his granddaughters is the journalist and novelist Isabelle Spaak, and one of his grandsons is the artist Anthony Palliser.

During the 1940s, during his time in New York with the United Nations, he also had an affair with the American fashion designer Pauline Fairfax Potter (1908–1976).

His son Fernand served in 1981 as chief of staff for Gaston Thorn, president of the European Commission, until he became the victim of his wife's murder–suicide on 18 July 1981.

Early life and education During the German invasion of Belgium in 1914, Spaak attempted to join the Belgian Army but was captured and spent the next two years as a prisoner of war in Germany. At the end of the war, Spaak was released from captivity and entered the Free University of Brussels, where he studied law. During the same period, Spaak was also a tennis star, and played for the Belgian team in the 1922 Davis Cup.

After receiving his law degree, Spaak practised as a lawyer in Brussels, where he "excelled in defending Communists charged with conspiring against the security of the realm", and others including Fernando de Rosa, an anarchist Italian student who attempted to kill Crown Prince Umberto of Italy during a state visit by the prince to Brussels.

Post-World War I Belgian politics He became a member of the Socialist Belgian Labour Party in 1920. He was elected deputy in 1932. In 1935, he entered the cabinet of Paul Van Zeeland as Minister of Transport. In February 1936 he became Minister of Foreign Affairs, serving first under Van Zeeland and then under his uncle, Paul-Émile Janson. From May 1938 to February 1939 he was Prime Minister for the first time. In 1938, he allowed Herman Van Breda to smuggle the legacy of Edmund Husserl out of Nazi Germany to Belgium through the Belgian Embassy in Berlin.

In social policy, a number of progressive reforms were realised during Spaak's first premiership. An Act of June 1938 "increased the functions of the National Society for Cheap Houses and Dwellings and empowered it, under State guarantee, to contract a loan of 350 million francs," while a Royal Decree of July 1938 laid down the rules for applying the provisions of a Holidays with Pay Act passed in 1936 to agricultural, horticultural and forestry undertakings. An Act of 20 August 1938 amended and supplemented the 1936 Holidays with Pay Act by extending its coverage to all undertakings, whatever their number of wage earners, as well as to home workers. The Act also removed a previous requirement in which a wage earner had to work for at least a year with the same employer in order to earn an annual holiday. The old-age, invalidity, and survivors' insurance program for miners was modified by an act passed on 8 July 1938, which increased the benefits available to invalids, the elderly, and widows who already received pensions while also significantly expanding the requirements for the granting of invalidity pensions.

An Order of 25 August 1938 prohibited the use of so-called motor spirit "for greasing, cleaning (hands) etc.," while a Royal Order of 27 August 1938 fixed normal weekly hours of actual work in the ship-repairing industry in Antwerp at 42 hours "distributed over the seven days of the week."

A Royal Order of 27 December 1938 extended the scope of an eight-hour Act passed in June 1921 to cover technical staff employed in cinemas, and a Royal Order of 22 December 1938 amended the entries in the second column of the schedule (list of occupations) which was now brought into conformity with Convention No. 42, and added "in the case of pneumoconiosis, sand-blasting processes in iron and steel foundries.

When he was Minister of Foreign Affairs from 1936 to 1940, Spaak adhered to the political independence of Belgium and carried on the long-standing Belgian policy of neutrality, with no formal military cooperation with France or the United Kingdom and no open hostility to the Germans. On 10 May 1940, Germany invaded Belgium, Luxembourg, the Netherlands and France. In disarray and with almost all of the country occupied, the Belgian Army — by the command of King Leopold III — surrendered on May 18, leading to a constitutional conflict with part of the government (including Spaak), which wanted to continue military operations together with France. The rump of the Belgian government regrouped in Limoges and Bordeaux and stayed close to the French, who surrendered on 22 June.

Again conflict arose in the Belgian government between those who wanted to stay in France (and maybe return to Belgium) — among these Spaak and Belgian Prime Minister Hubert Pierlot — and others who wanted to leave for London and to continue the war effort further. Minister Marcel-Henri Jaspar — done with the quarrelling — left on June 24 for London and tried to form a new government and obtain recognition from the British. For this, he was thrown out of the government at once by Pierlot and Spaak.

After the repeal of diplomatic status by the French, Spaak finally went to Britain. Travelling in difficult circumstances with Pierlot through Spain and Portugal, partially even in the false bottom of a truck, they arrived in London in October 1940.Stephen George, "Paul-Henri Spaak and a paradox in Belgian foreign policy." Review of International Studies 1.3 (1975): 254–271.

Post-World War II domestic policies After the war, he was Minister of Foreign Affairs under the subsequent ministers Achille Van Acker and Camille Huysmans. He was twice appointed Prime Minister as well, first from 13 to 31 March 1946, the shortest government in Belgian history, and again from March 1947 to August 1949. During his last government, two important pieces of housing legislation were enacted. The De Taeye Act of 1948 organised fiscal rebates, credit facilities, and premiums for social dwellings built either on private or public initiative, while the Brunfaut Act of 1949 established a central budgeting organisation for governmental social housing policy, shifted the financial burden of infrastructural works to the state, and organised the financing of the two National Housing Societies.Peter Flora, Growth to Limits. The Western European Welfare States Since World War II . Under a law of 16 June 1947 holiday duration was tripled for under 18 year olds, and doubled for those between the ages of 18 and 21. Holiday pay was also doubled for the first week by the law of August the 10th 1947.

A bill on war damage, agreed upon in October 1947, stipulated that owners of homes damaged by the war and took the initiative to restore them were entitled to compensation. In 1948, voting rights for women were introduced. An Act providing for the establishment of works councils was promulgated in September 1948, while a school building fund was set up that same year "to supply the material needs of secondary education." Also in 1948, the multilateral school was introduced.