Aix-la-Chapelle, Congress of (1818), a meeting of the members of the Quadruple Alliance—Great Britain, Austria, Prussia, and Russia. The congress agreed to remove the occupation armies that had been kept in France since the defeat of Napoleon in 1815. France was then admitted to the group, creating the informal Quintuple Alliance. Alexander I of Russia, sponsor of the Holy Alliance, tried unsuccessfully to turn this alliance into a police force to put down all democratic and liberal movements in Europe. The five countries did form the so-called Concert of Europe; they agreed to meet at intervals to preserve peace and to consider common problems.
Cook, James (1728 - 1779), a British navigator. Captain Cook accurately charted vast regions of the South Pacific; provided a basis for England's claim to Australia and New Zealand; and developed a diet that prevented scurvy among seamen.
Cid, El , the popular name of Rodrigo (or Ruy) Diaz de Bivar (1040 - 1099), a Spanish national hero.