The period following Roman rule, generally known as the Dark Ages or Early Middle Ages, lasted from about 400 to 1000.

The territory of what is now Switzerland shared a similar evolution with the rest of western Europe.

The first couple of centuries or so was a time of migration, moving in the general direction of east to west. Peoples were displaced as waves of new tribes arrived from Asia.

Switzerland was settled by different peoples, who brought not only new lifestyles, but also new languages.

Christianity which had arrived in Switzerland under the Romans, took root and spread, partly through the work of missionaries. The church, with its system of bishoprics and monasteries, became a major landowner with rights over all those who lived on its lands.

At the same time, noble families were increasing their power and building up their landholdings by conquest, inheritance and marriage.

For a brief period the Frankish king Charlemagne controlled much of Western Europe and took the title Emperor of the West in 800.

However, even under Charlemagne there was no idea of a state. At every level of society, relations between weak and strong were based on personal allegiance. The emperor ruled through a network of noble families.

Throughout the period, and beyond, the balance of power between kings, dukes and the church constantly shifted as each jockeyed to preserve its old privileges or to grab new ones.

A further level of power was added in 962 when the German king Otto I persuaded the Pope to crown him Emperor of what much later became known as the Holy Roman Empire.