Original sentence: The territory was settled by the East Slavs from the early middle ages and, in the 12th century, the Rurikid Principality of Galicia (Galich) was formed there, merged at the end of the century with the neighboring Volhynia into the principality of Galicia-Volhynia which existed for a century and a half
Edited sentence: He founded city of Vladimir (Volynski) and later Christianized the local people.The territory was settled by the East Slavs from the early middle ages and, in the 12th century, the Rurikid Principality of Galicia (Galich) was formed there by descendants ov Vladimir, merged at the end of the century with the neighboring Volhynia into the principality of Galicia-Volhynia which existed for a century and a half