Eastern Hungarians

"Eastern Hungarians" or "Eastern Magyars" is a broad term for groups of Hungarians who remained in Eastern Europe during the Migration Period and did not participate in the Hungarian conquest.

Friar Julian named the country of the Eastern Hungarians for Magna Hungaria (Great Hungary). It was roughly situated in the area of present-day Bashkortostan. Before the start of the Mongol Invasion, Julian was able to reach the territory bordered by the rivers Volga – Kama – Belaya – Ural as a companion to a Muslim priest. There he found the Hungarians and found, which the chronicles of the time referred to as Magna Hungaria. Julian was even able to communicate with them in Hungarian (despite the gap of at least 300–400 years since the split). He set off home anxious to give account on his mission, as well as the news he gathered about the upcoming invasion of the Mongols.

In the 8th century, the Savard Hungarians, one section of the Hungarian people, broke off and moved to the country south of the Caucasus. Contemporary Byzantine source reports that around the mid- tenth century the Hungarians maintained contact with the Savard Hungarians who remained in Eastern Europe.

According to the theory of Kummagyaria, before the Mongol invasion of Europe, the Hungarians who remained in Eastern Europe and did not participate in the Hungarian conquest possessed a country northwards from Caucasus. According to Laszlo Bendefy, the approximate location of Kummagyaria is the riparian area of the Kuma River, Southern Russia.
Papal bulls by Popes Innocent IV in 1253, Alexander IV in 1258 and Michael IV in 1288 and 1291 made reference to Kummagyaria, (spelled as Cummageria). A bull proclaimed by Pope John XXII in 1329 is addressed to Gyeretyán, who was the then chieftain of Kummagyaria.
Odorico Raynaldi wrote a commentary on the occasion of the bull’s proclamation:

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