The Nebelung is a modern re-creation of the longhaired Russian Blue cat, with its modern origins beginning in the mid-1980s. The foundation cats for the U.S. Nebelungs, Siegfried and Brunhilde, were born in 1984 and 1985. Although the longhaired Russian cat was exhibited in England over a century ago, it has not been part of the cat fancy until the latter part of this century.

It is a slender cat with a medium-long, silky blue coat. The TICA standard for the Nebelung is identical to that of the Russian Blue, except for the coat length.

Like the Russian Blue, Nebelungs make affectionate, devoted companions, though they may be initially shy with strangers, particularly young children. Nebelungs may take a little extra time to adapt to new homes. The breed is quite rare and is available currently only in the United States, Germany, the Netherlands and Russia.