The city of Groningen had already gained its independence from its formal landlord, the Bishop of Utrecht in the 12th century.
After the Habsburg victory in the Battle of Heiligerlee (1536) during the Guelders Wars, the city of Groningen and the Ommelanden came under the rule of Charles V, Holy Roman Emperor.
[1][4] They were joined in the Lordship of Groningen and ruled by a Stadtholder, but with preservation of their ancient rights and privileges.
[6] In March 1580, Stadtholder George van Lalaing succeeded in convincing the city of Groningen to leave the Union of Utrecht and to remain loyal to the King of Spain.
[7][8][9] The lordship was abolished but the city and the Ommelanden remained united in one province.