The European hamster, also known as the Eurasian hamster, black-bellied hamster or common hamster, is the only species of hamster in the genus Cricetus. It is native to grassland and similar habitats in a large part of Eurasia, extending from Belgium to the Altai Mountains and Yenisey River in Russia. Historically, it was considered a farmland pest and had been trapped for its fur. Its population has declined drastically in recent years and is now considered critically endangered. The main threats to the species are thought to be intensive agriculture, habitat destruction, and persecution by farmers.

The Cricetidae are a family of rodents in the large and complex superfamily Muroidea. It includes true hamsters, voles, lemmings, muskrats, and New World rats and mice. At over 870 species, it is the either the largest or second-largest family of mammals, and has members throughout the Americas, Europe and Asia.