Greater Netherlands

Greater Netherlands (Dutch: Groot-Nederland) or Dietsland ("Dutchland") is a hypothetical monolingual polity formed by fusing the two Dutch-speaking regions of Flanders and the Netherlands. The concept was originally developed by Pieter Geyl, who argued that the two only separated during the Eighty Years' War against Spain in the 16th century.

Although Geyl was strongly anti-Nazi and argued from a historical and cultural perspective, Nazi Germany built upon the idea during the Second World War with a focus on ethnic nationalism, still prominent among some in the political far right.

Despite the name, such a process was to be done via a merger of the two countries into a new entity rather than a Dutch annexation. The Greater Netherlands movement has long been divided on the political form the polity would take, considering among others a confederation, a federation, or a unitary state. More expansive and less common versions may include the additional fusion of French Flanders, Suriname, formerly Dutch-speaking areas of Germany and France, or even the ethnically Dutch and/or Afrikaans-speaking parts of South Africa.

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