FREDERICK III. (1515-1576), called "the Pious," elector palatine of the Rhine, eldest son of John II., count palatine of Simmern, was born at Simmern on Feb. 14, 1515. In 1537 he married Maria (d. 1567), daughter of Casimir, prince of Bay reuth, and in 1546, mainly as a result of this union, adopted the reformed doctrines. In 1557 he became count palatine of Simmern by his father's death, succeeding his kinsman, Otto Henry (1502-1559), as elector palatine two years later. Although inclined to the views of Calvin rather than to those of Luther, and as the breach between the followers of the two reformers became wider, he definitely adopted Calvinism. This form of faith was established in the Palatinate; in its interests the "Heidel berg Catechism" was drawn up in 1563; and Catholics and Luth erans were persecuted alike, while the churches were denuded of all their ornaments. The Lutheran princes wished to root out Calvinism in the Palatinate, but were not willing to exclude the elector from the benefits of the religious peace of Augsburg, which were confined to the adherents of the confession of Augs burg, and the matter came before the diet in 1566. Boldly defend ing his position, Frederick refused to give way an inch, and as the Lutherans were unwilling to proceed to extremities the emperor Maximilian II. could only warn him to mend his ways. The elector aided the Huguenots in France and the insurgents in the Netherlands with men and money; one of his sons, John Casimir (1543-1592), took a prominent part in the French wars of religion, while another, Christopher, was killed in 1574 fight ing for the Dutch at Mooker Heath. Frederick sought in vain to prevent the election of a member of the Habsburg family as Ro man king, to secure the abrogation of the "ecclesiastical reserva tion" clause in the peace of Augsburg, or to obtain for Protestants in the territories of the spiritual princes. He died at Heidelberg on Oct. 26, 1576.
See A. Kluckhohn, Friedrich der Fromme (Nordlingen, and Briefe Friedrichs des Frommen, edited by Kluckhohn (Brunswick, 1868-72).