Tannaea is the name of a historical region in southeast Marcasia, on the western shores of the Denurean Sea. The region covered an area approximately corresponding to the borders of modern-day Tannaea province, albeit slightly smaller. It was inhabitated first by the Eleena (known to the Areth as the Tann), but was later also settled by the Areth and various other ethnic groups. Today nearly a third of the region's population is dusleida.
The region has had a chequered history, being first conquered and dominated by the Lazeian Empire, then the Andu Empire, and subsequently reconquered in the campaign of Arithian Reunification. As part of the province of Tannaea, it achieved autonomy for the first time in over two thousand years, with the Arithian parliament's passage of the Devolution Act in 1979 CIE.
The area was probably first settled by the Eleena, but due to the lack of written records until the arrival of the Areth and a geology and climate notoriously unfriendly to archaeology, the assumption may never be either proven or disproven. The earliest surviving attested references to the region and the Eleena date back to the 5th century BCIE, coming from a diary wherein the royal explorer Azumats Ēporigates of the kingdom of Rabia-Satuka (in modern-day Mylaea) comments on the "cultural backwardness of a land and its people, who are called Tann". It is not known whence he arrived at the name, but the appellation stuck.
Areth influence and direct control would gradually spread into and through the region over the next three hundred years, through trade and colonialistic treaties of settlement and jurisdiction that granted the Areth considerable power, as well as extraterritoriality. Formal cession of the region to control of the Lazeian Empire occurred in 138 BCIE, and the region remained Areth territory until the fall of the Empire, when it passed, for 45 years, to the Andu Empire. Much of the territory was recovered by remaining Areth forces in the area, establishing the mediaeval (Areth) kingdom of Palacaea, which consisted exclusively of Tannaean land. The region remained in Areth possession through the reunification, but was unincorporated into the modern state until the Republican Revolution abolished the monarchy in 1886 CIE. By then, the new Tannaean province was already home to more than the Eleena: of the population of 4 million, more than 800,000 were of Areth descent, and a further 200,000 of other assorted foreign ancestry.
- See also Tannaea (province)#History for more information