Siegbert Tarrasch (German: [ˈziːɡbɐt ˈtaraʃ]; ۵ March ۱۸۶۲ – ۱۷ February ۱۹۳۴) was a German chess player, considered to have been among the strongest ones, and one of the most influential chess theoreticians of the late ۱۹th and early ۲۰th century.
Tarrasch was born in Breslau, in what was then Prussian Silesia and now is Poland. Having finished school in ۱۸۸۰, he left Breslau to study medicine in Halle. With his family, he settled in Nuremberg, Bavaria, and later in Munich, setting up a successful medical practice. He had five children. Tarrasch was Jewish, converted to Christianity in ۱۹۰۰، and was a patriotic German who lost a son in World War I, yet he faced antisemitism in the early stages of the Third Reich.