I just know that ottomans used to call scandinavians as "russian", they were not able to see any distinction between russians or them.
and before the turkish presence on anatolia, vikings were guarding hagia sophia, and they were calling constaninapolis as "miklagard", which means "big city" in old scandivian, constaninapolis' poplation was close to 1 million people even in ancient times.
And Constantinople named as Istanbul, it is also a different pronunciation of Constantinople. And official name of Istanbul remained as "Konstanniye" till the republic.
I think Viking were more related with ancient turks such as Huns or maybe seljukids.