1. Saxland (Saxony) and possibly Frakkland (lit. trans. 'the land of the Franks' - in now some eastern parts of France and in western part of Germany?) as well in some cases, in contrast to modern Icelandic Frakkaland that exclusively means France now; Garðaríki (Russia, lit. meaning is 'the land/ dominion of the towns (?)'); Frísland (Friesland)
2. While there will certainly always more to be said, the following previous posts might answer OP's question: The Danes or Vikings from later Denmark would often raid the Frankish Empire and later what would become the Holy Roman Empire. How were they so successful and how did the Danes avoid being conquered by the big powers?; Why didn't the Vikings invade Germany?
3. Do you have enough literature on Slavic and Baltic peoples around the Baltic (see also in: How active were baltic raiders prior to the Livonian and Teutonic orders arrival?) and the Finns (Sámi) and their interaction with the Scandinavians during the Viking Ages?

Add. References:

• Kålund, Kr (utg.). Alfræði íslenzk, i: Codex AM 194, 8vo. København, 1908.
• Kyrkjebø, Rune & Bjørg D. Spørck (overs.). Norrøn verdenshistorie og geografi: Veraldar saga, landafræði, Nikolás Bergsson, Leiðarvísir. Aschehoug: Oslo, 2012.

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