Ferdinand I (1503-1564) was the son of Philip I of Castile and Queen Joanna I of Castile, grandson of Emperor Maximilian I and younger brother of future emperor Charles V. When Charles V abdicated in 1556, Ferdinand was elected as his successor to the imperial throne, becoming Holy Roman emperor in 1558. Philippine Welser (1527 - 24 April 1580) was the morganatic wife of Ferdinand II, Archduke of Austria. She was granted the titles Baroness of Zinnenburg, Margravine of Burgau, Landgravine of Mellenburg and Countess of Oberhohenberg and Niederhohenberg.