Maybe TURKic and Altaic culture, look at map of of the Asian area of the world outside the Roman Empire and compare it to the modern map. The Timer period in the Roman Empire you should look at is 200 AD to 300 AD

Attila was a Hun.

The Huns maybe possibly the descendants of the Xiongnu people which there based around central Asia, or in towards terms Mongolia as shown on this map. They then later migrated into Turkey and Turkmenistan.

When the Roman Empire collapsed this left a power vaccum which caused the great migration and the setting up of the Hun capital in what is known today as Hungary.

Then Attila became leader he went on to form the Hunnic Empire as shown by these pictures.

sure i am on it