Buda

City · c. 1000 CE · in Europe

Capital of Kingdom of Hungary (1000–1526), Eastern Hungarian Kingdom (1529–1541).

Wroclaw (1000 CE): Capital of Duchy of Silesia (1139–1304), Duchy of Wroclaw (1169–1201).
Cagliari (c. 1000 CE): Capital of Giudicato of Cagliari (1000–1187).
Sant Martí d'Empúries (c. 1000 CE): Capital of County of Ampuria (1000–1078).
Gdańsk (997 CE): Capital of Free City of Danzig (1920–1939).
Dijon (c. 1003 CE): Capital of Duchy of Burgundy (1003–1477).
Kazan (1005 CE): Capital of Khanate of Kazan (1440–1551).
Qal'at Bani Hammad (1007–1090 CE): Capital of Hammadid Dynasty (1018–1151).
Bruges (c. 990 CE): Capital of County of Flanders (990–1384).
Le Mans (c. 990 CE): Capital of County of Maine (990–1481).
Blois (c. 990 CE): Capital of County of Blôis (990–1401).

Around the same time and place

Founding of the Holy Roman Empire (962 CE): Pope John XII crowned Otto I emperor in Rome, the conventional start of the Holy Roman Empire, which lasted until 1806.
Christianization of Kievan Rus' (988 CE): Vladimir the Great adopted Orthodox Christianity from Byzantium and had the people of Kyiv baptised in the Dnieper.
William the Conqueror (c. 1028 CE – 1087 CE): Duke of Normandy who conquered England in 1066 and became its first Norman king.
Trier (16 BCE – 1618 CE): Capital of Electorate of Trier (1333–1618).
Varangians to the Greeks (c. 800–1100 CE): Scandinavian traders and warriors travelled from the Baltic up the Neva and Volkhov past Novgorod, portaged to the Dnieper and sailed down past Kiev to the Black Sea and Constantinople.
Otto the Great (912 CE – 973 CE): German king who defeated the Magyars and was crowned emperor in Rome in 962; he was buried in Magdeburg.
Basil II (958 CE – 1025 CE): Byzantine emperor, called the Bulgar Slayer, who conquered the First Bulgarian Empire and brought Byzantium to its medieval height.
Amalfi (c. 960 CE): Capital of Republic of Amalfi (960–1033).