Andorra is the last independent survivor of the March states, a number of buffer states created by Charlemagne to keep the Muslim Moors from advancing into Christian France. Tradition holds that Charlemagne granted a charter to the Andorran people in return for their fighting the Moors. In the 800s, Charlemagne's grandson, Charles the Bald, named the Count of Urgel as overlord of Andorra. A descendant of the count later gave the lands to the diocese of Urgel, headed by the Bishop of Urgel.

In the 11th century, fearing military action by neighboring lords, the bishop placed himself under the protection of the Lord of Caboet, a Spanish nobleman. Later, the Count of Foix, a French noble, became heir to Lord Caboet through marriage, and a dispute arose between the French Count and the Spanish bishop over Andorra.

In 1278, the conflict was resolved by the signing of a pareage, which provided that Andorra's sovereignty be shared between the Count of Foix and the Bishop of Seo de Urgel. The pareage, a feudal institution recognizing the principle of equality of rights shared by two rulers, gave the small state its territory and political form.

Over the years, the title was passed between French and Spanish rule until, under the French throne of Henry IV, an edict in 1607 established the head of the French state and the Bishop of Urgel as co-princes of Andorra.

Given its relative isolation, Andorra has existed outside the mainstream of European history, with few ties to countries other than France and Spain. In recent times, however, its thriving tourist industry along with developments in transportation and communications have removed the country from its isolation.