The Duchy of Brabant was formed in 1183 as a state of the Roman Empire. It was divided between Belgium and the Netherlands with Antwerp and Brussels as its main cities. In 1830 there was a revolt against the Dutch rule. This resulted in the Duchy of Brabant gaining Belgian Independence.
The Grand Duchy of Moscow.
A duchy
Duchy of Racibórz was created in 1172.
Duchy of Silesia ended in 1918.
Duchy of Westphalia was created in 1180.
Duchy of Bielsko was created in 1572.
Duchy of Głubczyce was created in 1172.
Duchy of Zator was created in 1454.
Duchy of Zator ended in 1919.
Duchy of Limburg was created in 1065.
Duchy of Limburg ended in 1794.