The Renaissance tomb of count Niklas Salm in the side chapel, commissioned by Ferdinand I. after the Turkish siege in 1529.
Niklas (Nicholas), Count of Salm (1459-1530), was a German soldier and an Imperial senior military commander (German: Feldherr).
In 1529 aged 70, he was asked to organize the defense of Vienna during the first siege by the Turks, which he did with great skill and success.
During the siege, he was wounded by a falling rock, and died a few months later from his wounds.