This chapter introduces the long history of beaver and human interaction, discussing the folklore of First Nation peoples to whom the beaver was a sacred link to the Earth’s creation and the Catholic Church’s classification of them as fish; fur wars over their luxuriant pelts in North America; and the cultural beliefs of the use of their castoreum as a medicinal product, including curing all kinds of fever, relief of toothache, prevention of insomnia, and treatment of stomach disorders. This chapter identifies the historic and current distribution range of both beaver species, each of which, after avoiding near extinction in historic times, in this more modern era been widely reintroduced. Numerous beaver restoration projects have focused on the rebooting of their critical role as ecosystem engineers. Eurasian beavers have recently been restored to more than 20 countries in Europe, with minimum estimates of 1.5 million individuals globally. In North America, populations returned from a low of several hundred thousand at the beginning of the nineteenth century to now approximately 6 million beavers.