Judaism
Christianity was originally a sect of Second Temple Judaism, but the two religions diverged in the first century. The differences between Christianity and Judaism originally centered on whether Jesus was the Jewish Messiah but eventually became irreconcilable. Major differences between the two faiths include the nature of the Messiah, of atonement and sin, the status of God's commandments to Israel, and perhaps most significantly of the nature of God himself. Due to these differences, Judaism traditionally regards Christianity as Shituf or worship of the God of Israel which is not monotheistic. Christianity has traditionally regarded Judaism as obsolete with the invention of Christianity and Jews as a people replaced by the Church, though a Christian belief in dual-covenant theology emerged as a phenomenon following Christian reflection on how their theology influenced the Nazi Holocaust.
Jewish ethnic divisions
Smaller Jewish groups include the Georgian Jews and Mountain Jews from the Caucasus; Indian Jews including the Bene Israel, Bnei Menashe, Cochin Jews and Bene Ephraim; the Romaniotes of Greece; the ancient Italian Jewish community; the Teimanim from the Yemen; various African Jews, including most numerously the Beta Israel of Ethiopia; the Bukharan Jews of Central Asia; and Chinese Jews, most notably the Kaifeng Jews, as well as various other distinct but now extinct communities.