The country derives its name from the Boii, a Celtic tribe which in the earliest historical period inhabited part of the land. According to very ancient traditions accepted by the modern historians of Bohemia, the Boii, whose capital was called Boiohemum, were weakened by continual warfare with neighbouring tribes, and finally subdued by the Teutonic tribe of the Marcomanni (about 12 B.C.). The Marcomanni were afterwards expelled by other Teutonic tribes, and eventually Bohemia was conquered by Slavic tribes, of whom the Cechs (see CZECH) were the most important. The date of the arrival of the Cechs in Bohemia is very uncertain, and the scanty references to the country in classical and Byzantine writers are rather misleading than otherwise. Recent archaeological research has proved the existence of Slavic inhabitants in Bohemia as far back as the beginning of the Christian era. The Cechs appear to have become the masters of the country in the 5th century. The first of their rulers mentioned in history is Samo, who is stated to have defeated the Avars, a Turanian tribe which had for a time obtained the overlordship over Bohemia. Samo also defeated the Franks in a great battle that took place at Wogatisburg (630), probably near the site of the present town of Eger. After the death of Samo the history of Bohemia again becomes absolutely obscure for about 130 years. The next events that are recorded by the oldest chroniclers, such as Cosmas, refer to the foundation of a Bohemian principality by Krok (or Crocus) and his daughter Libussa. The latter is said to have married Premysl, a peasant who was found ploughing his field--a legend that is common in most Slavic countries. Beginning with this semi-mythic ruler, the ancient chroniclers have constructed a continuous list of Premyslide princes. Neither the deeds attributed to these princes nor the dates of their reigns can be considered as historical. Christianity. Wenceslas Boleslav. Vladivoj. Bretislav I.