Complex sentence: This mythology may have been influenced by Old Norse interactions with other linguistic groups, including northern Slavs, Finns, and Anglo-Saxons, and it is also likely that it was influenced by incoming Christian mythology as well.
Split into simpler sentences: This mythology may have been influenced by Old Norse interactions with other linguistic groups, including northern Slavs, Finns, and Anglo-Saxons. It is also likely that it was influenced by incoming Christian mythology as well.