Historically, left-wing nationalists have often emerged in European states whose borders had been formed by medieval dynastic unity, bringing together multiple linguistic and ethnic groups into one single state. During the 18th and 19th centuries, those centralised states began to promote cultural homogenisation. In reaction, some regions developed their own progressive nationalism. This often occurred in regions whose cultural, economic or sociological distinctiveness from the dominant culture had produced historical grievances (political discrimination such as the Irish Penal Laws, economic crisis such as the Irish Great Famine, or traumatic war deaths). The idea could gain ground that government by distant economic or aristocratic elites was responsible for current misfortune, but that self-rule could remedy the situation by allowing a more egalitarian or state-interventionist approach, better suited to local tastes or needs, than the royal or imperial state.