Greater Netherlands ideology (Dutch: Grootneerlandisme) is an irredentist nationalism which calls for the Netherlands to be superseded by a Greater Netherlands incorporating various European territories in modern-day Belgium, France, and Luxembourg and has sometimes encompassed extra-European territories such as South Africa, Indonesia, or the Democratic Republic of the Congo although its precise objectives have historically varied significantly. 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. It is currently considered a fringe ideology associated with certain far-right political groups in the Netherlands and Belgian Flanders.