The Taurians that guarded the Golden Fleece were Slavs, as were the men of the Baltic with whom Phœnicians and Greeks traded for amber. The forest lands of the North, that grey home of magic, wisdom and valour, hang like a dark background full of strange possibilities behind sunny Greece and clear-headed, practical Rome—and this was the Empire of the Slavs in the past, the Gardariki and Iotunheim (Giant-land) of the Norsemen. From one century to another they played a part of increasing importance among the peoples of Central and Eastern Europe and were feared as a strong, homogeneous race. Their power reached its zenith towards the end of the fifth century, before the tidal wave of the Hun invasion swept over Europe. At that time they held the mastery from the Alps to the mouth of the Elbe, and from the Baltic to the Black Sea. They were then one great people divided into several tribes speaking slightly differing dialects; but only a fraction of their number—the inhabitants of the present Dalmatia—was subject to the Emperor Nepos. The invasion of the Avars, who took possession of a large strip of the Slav possessions between the Danube and the Dniester, made the first breach in the unity of the great Slav family. Henceforth they were known as Northern, Eastern, and Southern, Slavs, and began to form separate nationalities. In the age of Charlemagne these nationalities had already crystallized into independent states, whose power and prosperity are recorded in history. The strongest of these was eventually Poland, extending far into the Russia of to-day. The Moravian Empire of Svatopluk, the Empire of Serbia, the kingdom of Croatia, and the Slavicized Bulgars in the South, together with the Grand-Dukedom of Muscovy (and the Wendish kingdom in North Germany), complete the family of Slav States. It would take too long to enter into the historical importance of all these states, but it is a characteristic proof of their power that not only European, but Asiatic, nations courted their favour.