Jacob ben Asher, also known as Ba'al ha-Turim as well as Rabbi Yaakov ben Raash (Rabbeinu Asher), was likely born in Cologne, Germany c.1269 and likely died in Toledo, Spain c.1343.[1][2]
He was an influential Medieval rabbinic authority. He is often referred to as the Baal ha-Turim' ("Master of the Rows"), after his main work in halakha (Jewish law), the Arba'ah Turim ("Four Rows"). The work was divided into 4 sections, each called a "tur," alluding to the rows of jewels on the High Priest's breastplate. He was the third son of the Rabbi Asher ben Jehiel (known as the "Rosh"), a German-born Rabbi who moved to Spain. Besides his father, who was his principal teacher, Jacob quotes very often in the Turim his elder brother Jehiel; once his brother Judah (see Tur Orach Chaim, § 417), and once his uncle Rabbi Chaim (ib. § 49). According to many, Jacob moved to Spain with his father and was not born there.
Some say Jacob succeeded his father as the rabbi of the Jewish community of Toledo (Zacuto), while others say his brother Judah ben Asher did. His brothers were also rabbis of different communities in Spain. He lived in abject poverty most of his life, and according to The Sephardic Community of Chios, is said to have fallen ill and died with his 10 companions on the island of Chios, in Greece, whilst travelling.[3]