The beaver previously inhabited a large area from Western Europe to the Sino-Mongolian border, but, by 1890, they were almost extinct everywhere. Many forms of human pressure - hunting for meat, fur and castoreum; destruction of beaver canals and small ponds; and deforestation - led to the beaver's dramatic decline in Europe.
Rarely does this animal species become an object of persecution by Swedish hunters. He is encountered only in the northern parts of the country, and far into the desolate areas, ever more displaced by increasing colonization.
G. Swederus, 1832
Beaver meat, fur, and castoreum were used in Scandinavia. Castoreum is a strong smelling material that is produced in a pair of castor sacs under the beaver’s tail and is used by beavers to mark territory. An ordinary beaver has castor sacs that weigh around 250 grams. Castoreum has been used in folk medicine for many thousands of years — for example, the Greek physician Hippocrates (460-370 BC) wrote about the substance. Historically it has been used to treat many diseases, including epilepsy, colic, and gynecological diseases, and as an antidote to poisoning.
Since the beaver's castor sacs are close to the tail and since the beaver's testicles are not visible, many thought that the beaver's castor sacs were testicles. In antiquity and the Middle Ages, it was a folk tale that the beaver would bite off his testicles and throw them to hunters who wanted his castoreum.
From 1800, the beaver was rare in Scandinavia.
As early as 1756, the naturalist Nils Gisler, a student of Carl Linneaus, expressed concern that the beaver was being hunted to extinction in Sweden. While previously ‘they never caught all the pairs at each place, and never touched the babies’, he wrote, now they wanted to ‘exterminate everything that can be obtained’ with the result that there were fewer and fewer beavers.
In other words, in the 18th century, people were already aware that the beaver was about to disappear, and spoke out in favour of preserving it:
(...) but now, since they have become so rare, they should be protected in those places in which they are still found, because of their medicinally useful castoreum and their beautiful skins; at a minimum it should not be legal to kill the young.
Johan Hollsten, 1768