flourished until the 11th century. It represents an early medieval archaeological culture which emerged in the region of the Lower Danube. In Bulgaria it is usually referred to as Pliska-Preslav culture. The Pechenegs, the Cumans and Uzes are also mentioned by historic chronicles on the territory of Romania until the founding of the Romanian principalities of Wallachia in the south by Basarab I around 1310 in the High Middle Ages, and Moldavia in the east, by Dragoş around 1352. High Middle Ages The Pechenegs, a semi-nomadic Turkic people of the Central Asian steppes, occupied the steppes north of the Black Sea from the 8th to the 11th centuries, and by the 10th century they were in control of all of the territory between the Don and the lower Danube rivers. During the 11th and 12th centuries, the nomadic confederacy of the Cumans and Eastern Kipchaks dominated the territories between present-day Kazakhstan, southern Russia, Ukraine, southern Moldavia and western Wallachia. It is a subject of dispute whether elements of the mixed Daco–Roman population survived in Transylvania through the Dark Ages to become the ancestors of modern Romanians or whether the first Vlachs and Romanians appeared in the area in the 13th century after a northward migration from the Balkan Peninsula. There is also debate over the ethnicity of Transylvania's population before the Hungarian conquest. There is evidence the Second Bulgarian Empire, at least nominally, ruled the Wallachian lands up to the Rucăr–Bran corridor until the late 14th century. In a charter by Radu I, the Wallachian voivode requests tsar Ivan Alexander of Bulgaria to order his customs officers at Rucăr and the Dâmboviţa River bridge to collect taxes following the law. The presence of Bulgarian customs officers at the Carpathians indicates Bulgarian suzerainty over those lands, though Radu's imperative tone implies a strong and increasing Wallachian autonomy. Under Radu I and his successor Dan I, the realms in Transylvania and Severin continued to be disputed with Hungary. Basarab was succeeded by Nicholas Alexander and Vladislav I. Vladislav attacked Transylvania after Louis I occupied lands south of the Danube, conceded to recognize him as overlord in 1368 but rebelled again in the same year. Vladislav's rule also witnessed the first confrontation between Wallachia and the Ottoman Empire, a battle in which Vladislav was allied with Ivan Shishman. After the Magyar conquest of the 10th and 11th centuries, Transylvania became an autonomous and