While on the one hand local dynastic families were struggling with each other for power and influence, the area was still prey to foreign incursions. 

The Saracens

In the confused conditions of the 9-10th centuries, parts of what is now Switzerland were threatened by "Saracens," Muslim colonists. Their precise origin and initial purpose remains a mystery, but they moved from a base in Provence, in southern France, towards northern Italy, seizing the western Alpine passes. In the east they went as far as Chur and almost reached St Gallen, before withdrawing west again.

They were eventually driven out by local Frankish armies. One of the Christian leaders who around 972 forced them off the Great St Bernard - then known as the Mons Jovis - was Bernard of Menthon, who later founded the hospice there, and gave his name to the pass (and much later to the dogs trained at the hostel who rescued travellers in the snow.) 

The Hungarians 

At about the same time another threat came from Hungarians, who had originally come from Asia, reached the Danube basin at the end of the 9th century and were still moving westwards. They destroyed Basel in 917, and later burnt down the monasteries of St Gallen and Rheinau. Their incursions only ended when they were routed by the German king Otto I in 955.