Johann Andreas Eisenmenger

Johann Andreas Eisenmenger (Mannheim, 1654 – Heidelberg, December 20, 1704) was a German Orientalist from the Electorate of the Palatinate, now best known as the author of Entdecktes Judenthum (Judaism Unmasked).

The son of an official in the service of the Elector of the Palatinate Charles I Louis (who had, in 1673, offered Spinoza a chair in philosophy at Heidelberg), Eisenmenger received a good education, despite the early loss of his father to plague when he was 12 years old. He distinguished himself at the Collegium Sapientiae at Heidelberg by his zeal for Hebrew studies and Semitic languages. He eventually mastered Hebrew, Arabic and Aramaic. He was sent by the Elector to England and Holland to pursue his studies there. He studied rabbinical literature with Jewish assistance for some 19 years both at Heidelberg and Frankfort-on-the-Main, under the pretense, it was rumoured, of wishing to convert to Judaism. In Holland he established amicable relations with figures like Rabbi David ben Aryeh Leib of Lida, formerly of Lithuania, and then head of the Ashkenazi community in Amsterdam. An intended sojourn in Palestine was interrupted by the death of his sponsor in 1680, who died in August of that year.

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