The Hungarians were seven tribes who migrated into the alluvial Carpathian plain around the 9th century. Mistakenly they were believed to be descended from the barbarian nomad Huns, who had occupied the region in the 5th century. From this the area and then they became known as Hungaria, and as Hungarians. Arabic sources of the time called them majjar which may refer to the Magyar, the name of one of the tribes, which came to be prominent among the seven.
Until 1204 their main contacts were with Byzantium to the south and the Holy Roman Empire to the west. But both had other concerns: the Byzantines with the Turks, the Empire with its own internal incohesion and the with rest of Europe. So, despite their interference in the Danube basin, the Hungarians survived.
Their main problems (in period) arose in the 15th century when Islam, having mopped up the Byzantine Empire, sought to expand north. Hungary fought back but weak kings proved ineffective defenders, and when the people turned to the Holy Roman Empire for succour, they did so at a time when its structure was all but fallen, and Europe had no time for adventures outside its own immediate borders.