JAECKLIN, JUD (Judah b. Judah; 14th century), Ulm moneylender. Jaecklin was first mentioned in 1375 when the city of Ulm (Germany) borrowed 2,500 gulden from him. On Sept. 5, 1376, he was put under an imperial ban by *Charles IV, at the request of a feudal enemy of Ulm, for nonpayment of a debt of 4,000 gulden. When the city refused to hand him over, Charles set siege to it; however, he was forced to withdraw and to repeal the ban a year later. As revenge Charles released Duke Henry of Werdenberg, whose lands had suffered most during the siege, from his debts to Jaecklin. In 1379 Jaecklin's residence permit for Ulm was not renewed. He removed to *Constance and in 1380 requested the aid of the municipality in retrieving his property from Ulm. In 1393 Ulm complained that Jaecklin had settled in *Noerdlingen without permission and without relinquishing his citizenship, and that he was libeling the city of Ulm there. As Ulm had previously confiscated his property, it considered that it had a right to collect the debts due to him.
E. Nuebling, Die Judengemeinden des Mittelalters (1896), 327–43; H. Dicker, Die Geschichte der Juden in Ulm (1937), 23–32; M. Stern, in ZGJD, 7 (1937), 244f.