Original sentence: Due to the decline of Moldavia during the civil war, the region reverted to Wallachia, with Chilia being co-ruled by Hungary and Wallachia.The region had previously belonged to Wallachia, but had been incorporated into Moldavia in the late 14th century
Edited sentence: Due to the decline of Moldavia during the civil war, the region was surrendered to Hungary.The region had been incorporated into Moldavia in the late 14th century