Though there were important regional differences across much of western Europe, politicians and citizens supported policies that brought together limited state planning, strong economic growth, and democratic government, and this political and social consensus accompanied the first tentative steps on the long road toward a more unified Europe.

A number of new financial arrangements and institutions encouraged slow but steady moves toward European integration, as did cooperation with the United States. To receive Marshall Plan aid, the European states were required by the Americans to cooperate with one another, leading to the creation of the Organization for European Economic Cooperation and the Council of Europe in 1948, both of which promoted commerce and cooperation among European countries.

European federalists hoped that the Council of Europe would evolve into a European parliament with sovereign rights, but this did not happen. Britain, with its still-vast empire and its close relationship with the United States, consistently opposed conceding sovereignty to the council. On the continent, many prominent nationalists and Communists agreed with the British view.

Frustrated in political consolidation, European federalists turned to economics as a way of working toward genuine unity. Christian Democratic governments in West Germany, Italy, Belgium, the Netherlands, and Luxembourg founded the European Coal and Steel Community in 1951 (the British steadfastly refused to join). The founding states quickly attained their immediate economic goal — a single, transnational market for steel and coal without national tariffs or quotas. Close economic ties, advocates hoped, would eventually bind the six member nations so closely together that war among them would become unthinkable.

In 1957, the six countries of the Coal and Steel Community signed the Treaty of Rome, which created the European Economic Community, or Common Market. The first goal of the treaty was a gradual reduction of all tariffs among the six in order to create a single market. Other goals included the free movement of capital and labor and common economic policies and institutions. The Common Market encouraged trade among European states, promoted global exports, and helped build shared resources for the modernization of national industries. European integration thus meant not only increased transnational cooperation but also bolstered economic growth on the national level.

In the 1960s, hopes for rapid progress toward political as well as economic union were frustrated by a resurgence of nationalism. French president Charles de Gaulle, re-elected to office in 1958, viewed the United States as the main threat to genuine French (and European) independence. He withdrew all French military forces from what he called an “American-controlled” NATO, developed France’s own nuclear weapons, and vetoed the scheduled advent of majority rule within the Common Market. Thus, the 1950s and 1960s established a lasting pattern: Europeans would establish ever-closer economic ties, but the Common Market remained a union of independent, sovereign states.