The late 19th century saw the emergence of the theory that the core of today's Ashkenazi Jews are descended from a hypothetical Khazarian Jewish diaspora which migrated westward from modern-day Russia and Ukraine into modern-day France and Germany. Linguistic and genetic studies have not supported the theory of a Khazar connection to Ashkenazi Jewry.
https://www.veteranstoday.com/2020/08/21/most-controversial-document-in-internet-history-the-hidden-history-of-the-incredibly-evil-khazarian-mafia/
I think maybe not 100% accurate with dates,but correct about nature of the things.
read also:
https://www.europereloaded.com/khazaria-2-0-planned-jewish-migration-israel-ukraine-first/
https://stolenhistory.net/threads/the-tartarian-origin-of-the-jews.4008/
https://christianitybeliefs.org/end-times-deceptions/the-star-of-david-deception/
claims that they were in fact believing in tengrism,but sources are more important: "practicing magic" and "human sacrifice" confirmed.
also important to notice:
And here about drinking blood:
https://en.wikipedia.org/wiki/Talk:Blood_libel#%22Jews_accusing_Jews%22_for_drinking_blood.
https://thebridgelifeinthemix.info/health/the-body/throwing-children-fire-tay-sachs-molech-khazars/
Some truth is here.
PS: For sure it existed and its religion were "jewish":
https://en.wikipedia.org/wiki/Khazars#Rise_of_the_Rus'_and_the_collapse_of_the_Khazarian_state
From your source
Linguistic and genetic studies done by who exactly ?
Well of course there are some "studies" claiming COW-ID "vaccine" is safe.
By linguists and geneticists.
https://forward.com/opinion/385706/the-khazarian-hypothesis-is-not-the-only-junk-science-origin-story-of-jews/
https://forward.com/opinion/382967/ashkenazi-jews-are-not-khazars-heres-the-proof/