That island on the map named "Nova Zemla" ("New Land" in Russian) is known to be inhabited and vegetated in the past, being today a frozen rock. USSR, before all that nuclear tests there, thoroughly studied island and kind of ancient buildings foundations and labirynts was found.
It is still unclear who exactly lived on Nova Zemla, but the Nenec tribes (asian race), who live on the North of continent, South from Nova Zemla, name them "sirtya" or "sikhirtya" and believe they was white race with light eyes and moved to continent from the Nova Zemla island in a very distant past, when climate severely worsened, and later travelled through Nenec lands to the North Ural mountains and "go under the ground/mountains". Similar ethnos appears in legends of Russians who lived near Ural mountains, from the European side of Ural ridge, that legends could be found in Pavel Bazhov's books cycle "The Mistress of the Copper Mountain" about miracles of Ural and misterious people lived inside mountains. There is also Russian legends about people named "Чудь белоглазая" ("Chud' beloglazaya" - "Strange white-eyed people") who also, as in Nenec legends could disappear under the ground. Ancient Russians also named Finns and Karels as "чудь" ("Chud'" - strange people), however, without any misterious abilities, probably just because they speak strange language. There is "Чудское озеро" ("Chudskoe ozero" -"Strange people lake") near Pskov, on the border with Estonia, populated with Estonians, who are genetically very close to Finns, actually Estonians are Finnish people who in ancient times moved to another side of Baltic sea and turned to agriculture.
May be, this ancient "strange white-eyed people" was ancestors of whole Finno-Ugric tribes family. Finno-Ugorians also formed not far from Ural mountains, and then some moved to Nothern and Southern Europe, becoming Finns and Hungarians (I mean etnicity, not citizenship), some settled in place, becoming Mordva, Zyrya, Marians and so on. All that tribes have quite unique languages that belong to Finno-Ugorian group, very distinct from any other Indo-European language.
So, it is possible that those who migrate from Nova Zemlya, was not native to that island too and migrated there from some unknown and distant Polar land, that later drowned or disappered for whatever reasons.
It is hard to tell what exactly Ancient Greeks meant under Hyperborea, I doubt they knew about Nova Zemlya, I don't think they knew even about White Sea or Ural. Polar day and night exist on the continent too. So, Greek Hyperborea probaly is a name for the whole Nothern Eastern Europe and Nothern Western Asia including Nothern Ural, Yamal and all that in the middle.
Also, map is hardly show real land that existed in 1595. It is probably just an attempt to depict legends by cartographer to show his expirience and self-importance. Cartographer could hear some legends about land to the North of Eurasia Arctic shores from Hungarians or Finns at the time.
That island on the map named "Nova Zemla" ("New Land" in Russian) is known to be inhabited and vegetated in the past, being today a frozen rock. USSR, before all that nuclear tests there, thoroughly studied island and kind of ancient buildings foundations and labirynts was found.
It is still unclear who exactly lived on Nova Zemla, but the Nenec tribes (asian race), who live on the North of continent, South from Nova Zemla, name them "sirtya" or "sikhirtya" and believe they was white race with light eyes and moved to continent from the Nova Zemla island in a very distant past, when climate severely worsened, and later travelled through Nenec lands to the North Ural mountains and "go under the ground/mountains". Similar ethnos appears in legends of Russians who lived near Ural mountains, from the European side of Ural ridge, that legends could be found in Pavel Bazhov's books cycle "The Mistress of the Copper Mountain" about miracles of Ural and misterious people lived inside mountains. There is also Russian legends about people named "Чудь белоглазая" ("Chud' beloglazaya" - "Strange white-eyed people") who also, as in Nenec legends could disappear under the ground. Ancient Russians also named Finns and Karels as "чудь" ("Chud'" - strange people), however, without any misterious abilities, probably just because they speak strange language. There is "Чудское озеро" ("Chudskoe ozero" -"Strange people lake") near Pskov, on the border with Estonia, populated with Estonians, who are genetically very close to Finns, actually Estonians are Finnish people who in ancient times moved to another side of Baltic sea and turned to agriculture.
May be, this ancient "strange white-eyed people" was ancestors of whole Finno-Ugric tribes family. Finno-Ugorians also formed not far from Ural mountains, and then some moved to Nothern and Southern Europe, becoming Finns and Hungarians (I mean etnicity, not citizenship), some settled in place, becoming Mordva, Zyrya, Marians and so on. All that tribes have quite unique languages that belong to Finno-Ugorian group, very distinct from any other Indo-European language.
So, it is possible that those who migrate from Nova Zemlya, was not native to that island too and migrated there from some unknown and distant Polar land, that later drowned or disappered for whatever reasons.
It is hard to tell what exactly Ancient Greeks meant under Hyperborea, I doubt they knew about Nova Zemlya, I don't think they knew even about White Sea or Ural. Polar day and night exist on the continent too. So, Greek Hyperborea probaly is a name for the whole Nothern Eastern Europe and Nothern Western Asia including Nothern Ural, Yamal and all that in the middle.
Also, map is hardly show real land that existed in 1595. It is probably just an attempt to depict legends by cartographer to show his expirience and self-importance. Cartographer could hear some legends about land to the North of Eurasia Arctic shores from Hungarians or Finns at the time.