Ludwig III. (*1530, +1611) was a grandson of Count Ludwig. As a result of his marriage to Anna, the daughter and heiress of the Count of Stolberg-Königstein-Wertheim, he inherited the county of Wertheim.
By 1580, he had assumed the name Count Löwenstein-Wertheim.
After the death of Count Ludwig III., there was a property settlement on 10 October 1611 in which his possessions were divided between his sons, Count Christoph Ludwig (*1568, +1618) and Count Johann Dietrich (*1584, +1644), the founders of the two existing lines of the House of Löwenstein. Count Christoph Ludwig is regarded as the progenitor of the Protestant line, subsequently known as the Princes of Löwenstein-Wertheim-Freudenberg.