The Rugini were only mentioned once, in a list of yet to mission tribes drawn by monk Bede

Bede

Bede , also referred to as Saint Bede or the Venerable Bede , was a monk at the Northumbrian monastery of Saint Peter at Monkwearmouth, today part of Sunderland, England, and of its companion monastery, Saint Paul's, in modern Jarrow , both in the Kingdom of Northumbria...

 (also Beda venerabilis) in his Historia ecclesiastica of the early 8th century:

Sunt autem Fresones, Rugini, Danai, Hunni, Antiqui Saxones, Boructuari; sunt alii perplures hisdem in partibus populi paganis adhuc ritibus servientis.

Whether the Rugini were remnants of the Rugii is speculative. The term Rugini was also interpreted as the first mention of the Slavic Rani (also Rujani)

Rani (Slavic tribe)

The Rani or Rujani were a West Slavic tribe based on the island of Rugia and the southwestern mainland across the Strelasund in what is today northeastern Germany....

, who in the Middle Ages

Middle Ages

The Middle Ages is a periodization of European history from the 5th century to the 15th century. The Middle Ages follows the fall of the Western Roman Empire in 476 and precedes the Early Modern Era. It is the middle period of a three-period division of Western history: Classic, Medieval and Modern...

 dwelled on the isle of Rügen

Rügen

Rügen is Germany's largest island. Located in the Baltic Sea, it is part of the Vorpommern-Rügen district of Mecklenburg-Vorpommern.- Geography :Rügen is located off the north-eastern coast of Germany in the Baltic Sea...

.