In the late migration period, areas which had previously been settled by Germanic tribes became settled by Slavs. In the case of Rugia and the adjacent mainland, where the Rugii were recorded before the migration period, Slavs first appeared in the ninth century; continuous settlement from the pre-Slavic era is suggested based on pollen analyses and name transitions, so a Rugian remnant seems to have been assimilated. The tribal name of the former inhabitants, the Rugii, might be the root of both the medieval name of Rugia and the tribal name of the Slavic Rani, though this hypothesis is not generally accepted.
Religion
The Rani believed in multiple gods, all of which had several faces and were worshipped as tall wooden statues in their respective temples. They were worshipped in temples, holy groves, at home and in ritual meals. The mightiest among their gods was Svantevit, a four-headed god having his temple at Cape Arkona in the northernmost part of his isle of Wittow. This temple was worshipped and collected tributes not only from the Rani, but from all Baltic Wends after Rethra, which previously had been the main Wendish religious centre, was destroyed in a German raid in 1068/9. Other gods were Tjarnaglofi with his temple on Jasmund near today's Sagard, further there were Rugievit, Porevit and Porenut with temples in the capital, Charenza, and other gods with temples all over the Rani realm. After the forced Christianization, monasteries and churches replaced the temples. In the church of Altenkirchen, a large stone from Arkona was used with a relief showing a Svantevit priest.
Administration and culture
Medieval chronicler Helmold of Bosau described the Rani as the only Wendish tribe ruled by a king and describes them as subduing many others while not tolerating subordinance themselves. Common decisions of the Wendish tribes were only made with the approval by the Rani. The mightiest position however was held by the High Priest called Drvovid, who stood above the king. The oracle decided if and where campaigns were mounted, and after a victory the monetary and noble metal part of the loot was given to the temple before the rest was partitioned. Subdued tribes were made subordinate to the temple. The Rani political capital was Charenza. Rani dukes also resided at Rugard castle, a precursor of the modern city ofBergen. Throughout the Rani lands there were castles, all having a ring-like wall of wood and clay, protecting villages and/or religious sites, and functioned as strategic strongholds or seats of the gentry. The Rani also established a main, mixed Slavic and Scandinavian trading center in Ralswiek. In the 11th and 12th centuries, they also raided their neighbors in a Viking manner.
In 955, Rani participated in the Battle of Recknitz, assisting German Otto I in defeating the Obotrites at the Recknitz River. As the Obodrite state expanded in the late 11th century, the Rani were also pressed and in 1093 had to pay tribute to Obodrite prince Henry. They launched a naval expedition in 1100, in the course of which they sieged Liubice, a predecessor of modern Lübeck and then the major Obodrite stronghold. This attack was however repulsed. In 1123, the Rani struck again and killed Henry's son Waldemar. When in 1123/24 an Obodrite army led by Henry reached the Rani territory, the Svantevit priests were forced to negotiate a peace. Henry's army consisted of 2,000–6,000 men, devastated the coastal settlements, and the terms of the subsequent agreement were that the island would only be spared in return for an immense sum which had to be collected from the continental Slavs further east. Regrouping after Henry's death, the Rani again assaulted and this time destroyed Liubice in 1128. At this time they seem to have been devoted pagans, with their priests holding theocratic powers. topples the god Svantevit at Arkona. Painting by Laurits Tuxen. In 1136, the Danes defeated the Rani, who in turn had to promise to adopt Christian faith—yet returned to their pagan beliefs as the Danish headed back. A force of Rani attacked the Danish fleet during the 1147 Wendish Crusade. Saxon armies repeatedly managed to raid Rugia. The Danes, who had assaulted the Rani already in 1136 and 1160, finally conquered the Rani stronghold of Arkona in 1168, forced the Slavs to become vassals of Denmark and to convert to Christianity. The wooden statues of their gods were burned and monasteries and churches were built throughout the Rani lands. The former Rani realm henceforth became the Danish Principality of Rugia.