The khazars where a Turkic people, is it jews you want to know about or khazars.....? There are varying accounts on the khazars, some say that when their empire collapsed under the pressure from Attila and his Huns and the Black Death, they moved towards Europe becoming today's Ashkenazi Jews, which makes sense since this is certainly the road they traveled from the Middle East to Europe, through the Caucasus. Some maintain that they where a Turkic people, but this is contradictory to the fact that all of khazars a converted to Judaism. As for the origins of Jews, they originally came from the Levantine coast, from a country called Israel, as you may know. The Jews are no "special" or very "homogenous" race as many may think, their just another middle eastern amalgamy of J1 , J2 , E3b and some are R1a or R1b. Regardless of wether it is J1 or J2 about 35-45% of Jewish men are haplogroup J, indicative of middle eastern origins. Another 20-30% are north-African E3b. 10-15 maybe 20% of them are R1b or R1a , European Jews in particular ( Sephardic and Ashkenazi) may have been subjected to Germanic/European blood. There are many different old Jewish communities known as "diasporas" that left Judah and Israel at different times during history due to persecutions or for other reasons. These communities can slightly/moderately differ in their genetic compositions depending on where they moved and which people's they where subjected to. There are also kurdish Jews, Mizrahim jews ( middle-eastern, etc) the Ashkenazi Jews moved from the Caucasus into east-central Europe long ago, the Sephardic Jews somehow reached Iberia (Spain/Portugal) there are also Jews in Yemen etc. predominantly they are a patrilineal amalgamy of J1, J2, E3b and sometimes European elements (R1a/1b) and/or rarer haplogroups, such as G for example ( at lower levels). Their genetic admixture thus indicates a probable middle eastern/ North African mix with later added European blood in certain diaspora communities.