Right after the war, a lack of numbers of Russian Blues led to cross breeding with the Siamese. Although Russian Blues were in the United States before the war, it was not until the post-war period that American breeders created the modern Russian Blue that is seen in the United States today. American breeders combined the bloodlines of both the Scandinavian and British Russian Blues. The Siamese traits have now largely been bred out. The short hair and slate-gray/blue color is often seen in mixed-breed cats, which can affect breeders and showers due to mislabeling a cat as a Russian Blue.