It is disputed if this Jacza is identical to the later Jaksa of Miechów (1120-1176) of the Gryfici (Świebodzice) noble clan, a knight of the Order of the Holy Sepulchre.

After losing the castle Brandenburg to Albrecht the Bear in battle in 1157, Jacza retreated out of the region and would transfer the principality to the dukes of Pomerania.

Jacza could be derived from the Slavic root iskati meaning to strike/split/sliver [stones], to make sparks/light, to glitter/shine and is related to such ancient names as Iskra (spark), Iškur (lord of the sparks/thunderbolts).

The territory of the Principality of Copnic consisted of central and eastern parts of modern day Brandenburg around the river Spree.

In the late 12th century, in the west it bordered other territories of the Polabian Slavs, which were annexed into the Germanic Holy Roman Empire.