The latter had no regular leaders; but at the approach of the enemy the inhabitants of each canton flew to arms, like the members of a single family; and all the feudal forces brought against them failed to subdue this popular militia.
The frequent result of these collisions was the refusal of the Frisons to recognize any authority whatever but that of the national judges.

Each canton was governed according to its own laws.

If a difficulty arose, the deputies of the nation met together on the borders of the Ems, in a place called "the Trees of Upstal" (_Upstall-boomen_), where three old oaks stood in the middle of an immense plain.

In this primitive council-place chieftains were chosen, who, on swearing to maintain the laws and oppose the common enemy, were invested with a limited and temporary authority.
It does not appear that Friesland possessed any large towns, with the exception of Staveren.

In this respect the Frisons resembled those ancient Germans who had a horror of shutting themselves up within walls.