The two invasions have noticeable differences along with some similarities. They are different in the sense that the Mongol invasions caused disunity and did not benefit any of the lands they conquered in central Asia, Russia, Persia because they wrecked more havoc than any benefits in the long run by permanently damaging lands that took centuries to recover from, they spread the bubonic plague to various regions killing millions through biological/chemical warfare and since they were constantly moving and did not have permanent settlements. The Mongols began migrating and conquering different lands because much of their grazing and farming lands had become occupied or used up. Unlike the Vikings, the Mongols used their conquered peoples (the Persians) to run their government to keep it stabilized.
Similar to the Vikings; they imposed their authority through their ferocity and their swift hit and runs. They were both very mobile groups who rarely settled in permanent settlements and stuck to quick hit and run attacks at unexpected times on their enemies. Both groups went out for land and for goods that they invade and take control of because they could not manufacture specific goods they needed or wanted. The Vikings unlike the Mongols, actually benefited northern Europe in the long run by causing the unity of the Germanic peoples of England who put their differences aside in order to defend themselves against the Vikings, similar to that in Germany where the invasion ended Carolingian rule, but lead to the unity of an effective state to defend against the Vikings. The invasions encouraged decentralized political order in France and led to the rise of local authorities. Unlike the Mongols who attacked on land, the Vikings were sea raiders.
The Vikings were originally Norse merchants and traders, but as the developed fantastic sea skills in building ships and sailing them, they became raiders who plundered lands opposed to the Mongols who were always fierce enemies of Asia who were always raiding lands. The Vikings set out to find new lands and raid them due to population pressures and oppressive Christian churches the imposed Christianity and wanted to destroy the Vikings pagan beliefs.
Bentley, Jerry H. and Ziegler, Herbert F. A Global Perspective on the Past. McGraw-Hill, 2006. Pages 440-443