Hebrew name: יעב"ץ
Years: 1697–1776
Primary city: Altona
Rabbi Yaakov Emden, son of Rabbi Tzvi Ashkenazi, was a private scholar in Altona. His extensive literary output, including his Siddur Beis Yaakov and the responsa Sheilas Yaavetz, remains a cornerstone of halachic and liturgical study. He is remembered for his uncompromising opposition to the Sabbatean movement, which culminated in a confrontation with Rabbi Yonasan Eibeschutz.