Climate was warm and the average temperature was around 18 degrees Celsius in July, compared with only 16 degrees today. Winters were mild, and snow rare.
Most of the plants and animals of today existed in Sweden at this time as well. Some heat-loving species were common, for example the pond turtle. Great-fen sedge, mistletoe and ivy were common heat-loving plants.
The oak formed dark forests usually intermixed with ash, elm and lime and covering vast areas. The warm climate allowed the species to spread up to southern Norrland and even further along the coast. Wild boar, aurochs and European bison grazed the woods.