Complex sentence: The Jewish Peril is the first edition (1920) of the so-called Protocols of the Elders of Zion, and its title is an antisemitic and pejorative ethnic slur.
Split into simpler sentences: The Jewish Peril is the first edition (1920) of the text commonly referred to as "The Protocols of the Elders of Zion". Its title is an antisemitic and pejorative ethnic slur.