Marquard Rudolf von Rodt came from Upper Swabian knightly nobility of the Freiherren von Rodt zu Bußmannshausen. His father was Johann Dietrich, knight chief and heir of Kempten Abbey; His mother was Maria Barbara von Westerstetten.
Marquard Rudolf was recorded in 1653 as an ex-spectant of the Constituency of the Cathedral. He gave his first profession in 1666 and studied at the University of Strasbourg. After becoming sub-deacon and deacon, he was admitted to the chapter of Second Profession. On 26 May 1668, he received the ordination of priest. From 1668 onward, he was a canon in Augsburg and, since 1660, by his episcopal nomination, in Konstanz as well as cantor (1673), archdeacon (1683), and, from 1686, dean at the Konstanz Minster. In 1686 he became president of the clergy council in Constance.[2]
In addition to the bishop's office, he was "Lord of the Reichenau (domini Augia maioris) and Öhningen."[4]
His episcopal office was marked by political disputes with France. In addition, the treasury of the imperial court at the Hochstift burdened his work.[5]
Marquard Rudolf died in Hegne Castle and was buried in the cathedral at Constance.