What Has a Map of the Khazar Empire to Do with "Palestine"?

If you visit this site, you'll observe a list of maps of Palestine.

And at the bottom you can see one of the Khazarian Empire:

Background:

In 1976, Arthur Koestler...in The Thirteenth Tribe, argued that most Ashkenazi Jews are descended from the Khazars, a Central Asian people who ruled a large kingdom on the Black Sea and apparently converted to Judaism in the 8th century. This hypothesis has been taken up more recently by Shlomo Sand in a book called The Invention of the Jewish People. Koestler, one of the oddest and most extraordinary public intellectuals of the 20th century, wanted to weaken anti-Semitism by demonstrating that many Jews weren’t Semites at all. Sand, a self-avowed post-Zionist who teaches at Tel Aviv University, is apparently driven by the desire to prove that Ashkenazi Israelis are interlopers in the Middle East. 

An anti-Semitic canard, it has been going through yet another revival.

Al Jazeera and many other Arabs believe it as it would justify their claim of European Jews being a foreign entity as it is for Russian nationalists, a:

pretext for arguing that Jewish intrigues and dominance were to be found from the very beginning of Russian history. In this context the term “Khazars” became popular as a euphemism for the so-called “Jewish occupation regime.”

That's why you will read of pro-Palestine propagandists demanding Jews of Israel 'go back to Europe'. 

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