Asia had been in vassalage; in the case of Israel at least since Menahem (2 Kings xv.
Arabia, and reducing that country to a state of vassalage: the king is styled in Ethiopian chronicles Caleb (Kaleb), in Greek and Arabic documents El-Esbaha.
In 1503 we find him fighting in Corsica in the service of Genoa, at that time under French vassalage, and he took part in the rising of Genoa against the French, whom he compelled to evacuate the city.
The abolition of the Holy Empire in 1806 removed even the shadow of vassalage from the German reigning dukes, who retain their sovereign status under the new empire.
But vassalage could only be a cause of disintegration, not of unity, and that this disintegration did not at once spread indefinitely was due to the dozen or so great military commands Flanders, Burgundy, Aquitaine, &c.which Charles the Bald had been obliged to establish on a strong territorial basis.