Difference and Comparison side by side
The Siberian is a landrace variety of domestic cat, present in Russia for centuries and more recently developed as a formal breed, with standards promulgated since the late 1980s.
They vary from medium to medium-large in size.A longer name of the formal breed is Siberian Forest Cat, but it is usually referred to as the Siberian or the Siberian cat.
The Norwegian Forest cat (Norwegian: Norsk skogkatt or Norsk skaukatt) is a breed of domestic cat originating in Northern Europe. This natural breed is adapted to a very cold climate, with top coat of glossy, long, water-shedding hairs and a woolly undercoat for insulation. Although this is uncertain, the breed's ancestors may have been a landrace of short-haired cats brought to Norway by the Vikings around 1000 AD, who may also have brought with them long-haired cats, like those ancestral to the modern Siberian and Turkish Angora breeds.