URSINUS, Zacharias (1534-1583), German theologian, and one of the authors of the Heidelberg Catechism (see vol. V. p. 219), was a native of Breslau, and became a disciple of Melanchthon at Wittenberg. He afterwards studied divinity at Geneva under Calvin and Hebrew at Paris under Mercier. In 1561 he was appointed professor in the Collegium Sapientiae at Heidelberg, where in 1563 at the instance of the elector-palatine, Frederick III., he drew up the Catechism in cooperation with Kaspar Olevian. The death of the elector in 1577 led to the removal of Ursinus, who from 1578 till his death in 1583 occupied a professorial chair at Neustadt-an-der-Haardt. His Works were published in 1587-89, and a more complete edition by his son and two of his pupils, Pareus and Reuterus, in 1612.