The first Hunnic king about whom scholars have any detailed knowledge is Ruga, (also known as Ruglia). Living arrangements for the Huns changed with Ruga’s accession.
In exchange for allowing his warriors to fight on behalf of the Eastern Roman Empire, Ruga negotiated a treaty (in 433) which gave the Huns a permanent homeland. It was a triumph for him and an unprecedented event for the nomadic Huns.
Ceding a part of Pannonia (known at the time as Pannonia Secunda and today as the Carpathian Basin) to Ruga and his people, the empire in the east was not relieved of its Hunnic tribute obligations. Every year the Huns collected 350 pounds of gold from the empire, simply for agreeing not to attack the capital city of Constantinople.
The Huns were given land near the Danube River, in today’s Hungary. It is believed they settled on the plains between Budapest and Szeged (today a lovely university town located on the banks of the Tisza River).
Scholars doubt that individual tribes of Huns were already consolidated into one kingdom under Ruga. That would happen a bit later, under his nephew Attila.