generals did what they could by means of defensive works on the frontiers, of punitive expeditions, and of trying to set the various hordes of barbarians at loggerheads with each other, but, as they had at the same time to defend an empire which stretched from Armenia to Spain, it is not surprising that they were not more successful.  The growing riches of Constantinople and Salonika had an irresistible attraction for the wild men from the east and north, and unfortunately the Greek citizens were more inclined to spend their energy in theological disputes and their leisure in the circus than to devote either the one or the other to the defence of their country.  It was only by dint of paying them huge sums of money that the invaders were kept away from the coast.  The departure of the Huns and the Goths had made the way for fresh series of unwelcome visitors.  In the sixth century the Slavs appear for the first time.  From their original homes which were immediately north of the Carpathians, in Galicia and Poland, but may also have included parts of the modern Hungary, they moved southwards and south-eastwards.  They were presumably in Dacia, north of the Danube, in the previous century, but they are first mentioned as having crossed that river during the reign of the Emperor Justin I (518-27).  They were a loosely-knit congeries of tribes without any single leader or central authority; some say they merely possessed the instinct of anarchy, others that they were permeated with the ideals of democracy.  What is certain is that amongst them neither leadership nor initiative was developed, and that they lacked both cohesion and organisation.  The Eastern Slavs, the ancestors of the Russians, were only welded into anything approaching unity by the comparatively much smaller number of Scandinavian (Varangian) adventurers who came and took charge of their affairs at Kiev.  Similarly the Southern Slavs were never of themselves able to form a united community, conscious of its aim and capable of persevering in its attainment.

The Slavs did not invade the Balkan peninsula alone but in the company of the Avars, a terrible and justly dreaded nation, who, like the Huns, were of Asiatic (Turkish or Mongol) origin.  These invasions became more frequent during the reign of the Emperor Justinian I (527-65), and culminated in 559 in a great combined attack of all the invaders on Constantinople under a certain Zabergan, which was brilliantly defeated by the veteran Byzantine general Belisarius.  The Avars were a nomad tribe, and the horse was their natural means of locomotion.  The Slavs, on the other hand, moved about on foot, and seem to have been used as infantry by the more masterful Asiatics in their warlike expeditions.  Generally speaking, the Avars, who must have been infinitely less numerous than the Slavs, were settled in Hungary, where Attila and the Huns had been settled a little more than a century previously; that is to say, they were north