Cagliari

City · c. 1000 CE · in Europe

Capital of Giudicato of Cagliari (1000–1187).

Wroclaw (1000 CE): Capital of Duchy of Silesia (1139–1304), Duchy of Wroclaw (1169–1201).
Buda (c. 1000 CE): Capital of Kingdom of Hungary (1000–1526), Eastern Hungarian Kingdom (1529–1541).
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

Reconquista (718–1492 CE): Centuries-long series of campaigns by Christian kingdoms to take the Iberian Peninsula from Muslim rule, ending with the fall of Granada in 1492.
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.
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).
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.
Amalfi (c. 960 CE): Capital of Republic of Amalfi (960–1033).
Luxembourg (963 CE): Capital of Duchy of Luxembourg (1429–1449).
Stephen I of Hungary (c. 975 CE – 1038 CE): First king of Hungary, crowned in 1000 or 1001, who converted his people to Christianity; venerated as Saint Stephen.