West Kostenia

West Kostenia (Kostenian: Vorez Kastanja), officially the Socialist Federal Republic of Kostenia (Kostenian: Polokol Izevisk Barenj Kastanja), is a Constituent Republic and federated state of the Socialist Federation of Sentryzija. It is located in the northeast of Sentryzija and claims to be the nation state of the Kostenian people.

The Kingdom of Kostenia formed in 517 in the aftermath of the death of Hanovak the Great and the collapse of the Arolian Empire. The Kingdom remained one of the dominant Sorillian states until the 16th century when it began to decline. In 1674 The King of Kostenia died leaving no apparent heir. This lead to a succession crisis and a war between Troiya and Obradina. Kostenia would switch hands multiple times across the centuries as the region would remain contested up to the modern day. In 1912 during the Obradinian Civil War Kostenian Liberals and Nationalists would form the Republic of Kostenia, however it would be short lived as later that same year Troiya would invade during the chaos and destroy the fledgling Republic. From this point onwards Kostenia would remain divided and its modern border set. In 1918 the Socialist Federation of Sentryzija was founded and the Kostenians granted an autonomous Republic.

In modern times, West Kostenia is known for its mining industry, Communist politics and lively musical culture. Kostenia has the 5th highest GDP in Sentryzija, behind Marizenja but ahead of the Troiyan Free Cities.