Leo Jud (also Leo Juda, Leo Judä, Leo Judas, Leonis Judae, Ionnes Iuda, Leo Keller) (1482 – June 19, 1542), known to his contemporaries as Meister Leu, Swiss reformer, was born in 1482 in Guémar, Alsace, southwest of Strasbourg.
Like his later colleague Heinrich Bullinger, Jud is the son of a priest.
His father, Johannes Jud, is from Guémar and his mother, Elsa Hochsang, is from Solothurn.
He studies at the Latin school in Sélestat with Martin Bucer and in 1499 he matriculates at the University of Basel, where he meets Huldrych Zwingli.
He begins his studies in medicine but switches to theology under the influence of Thomas Wyttenbach.
Leo Jud is one of the lesser-known leaders of the Swiss Reformed Church, but his influence is extensive.
