On April 8, 1904, with war in Europe a decade away, Britain and France sign an agreement, later known as the Entente Cordiale, resolving long-standing colonial disputes in North Africa and establishing a diplomatic understanding between the two countries.

Formally entitled a Declaration between the United Kingdom and France Respecting Egypt and Morocco, the Entente Cordiale of April 1904 amounted more than anything to a declaration of friendship between these two great European powers. By its terms, France promised not to challenge British control over Egypt; for its part, Britain recognized France’s right, as a Power whose dominions are conterminous for a great distance with those of Morocco to act in that country to preserve order and to provide assistance to bring about whatever reforms in the government, economy or military it deemed necessary.

Through the Entente Cordiale, Britain and France established the beginnings of an alliance, promising, in the concluding words of the agreement, to afford to one another their diplomatic support, in order to obtain the execution of the clauses of the present Declaration regarding Egypt and Morocco. The agreement stopped short, however, of requiring the two nations to provide military support to each other; this aspect of the alliance would come later.

A motivating factor behind the agreement was undoubtedly France’s desire to protect itself against possible aggression from its old rival, Germany, who had steadily been growing stronger in the years since its victory in the Franco-Prussian War of 1870-71 and now possessed the most powerful land army in the world. Britain was also eager to keep Germany in check, especially in light of a revamped, ambitious German naval program, which—if successful—threatened to challenge Britain’s clear dominance at sea.

The German government, anxious over this agreement, decided to test its limits, sending Kaiser Wilhelm II to Morocco in March 1905 to declare his support for the sultan—a clear challenge to France’s influence in that country, which had been sanctioned by the Entente Cordiale. This bid to shake the Anglo-French alliance failed, as Britain sided with France; an international conference that convened at Algeciras, Spain, the following year also recognized France’s claims in the region.

The clash between Germany and the new allies became known as the First Moroccan Crisis—a second occurred in the summer of 1911, when both France and Germany sent forces to Morocco—and resulted in a tightening and solidifying of the Entente Cordiale, as Britain and France, aiming to confront German aggression, moved from mere friendship to an informal military alliance and, later, to talks and an agreement with France’s ally, Russia. By 1912, then, two powerful and hostile blocs had been formed in Europe, with France, Britain and Russia on one side, and an increasingly isolated Germany—with relatively lukewarm support from Austria-Hungary and Italy—on the other. Two years later, this volatile situation would erupt into the First World War.