Colloredo-Man(n)sfeld is an Austrian (former Bohemian) Princely dynasty which according to – unverified – family tradition descends from the Swabian Lords of Waldsee. Allegedly one Liebhart (Liobardo) of Waldsee came to Italy attendant King Conrad II and about 1031 was enfeoffed by Patriarch Poppo of Aquileia with Mels Castle near Udine in Friuli. His descendants from 1302 onwards had nearby Colloredo Castle erected as their residence.
The Colloredo family achieved the elevation to the noble rank of Freiherren by the Habsburg Emperor Rudolf II in 1588 and became immediate Reichsgrafen in 1724. Rudolph Joseph von Colloredo (1706-1788), Vice-Chancellor of Empress Maria Theresa, was appointed Prince of the Holy Roman Empire in 1763. The Colloredo-Mansfeld line emerged when his son Franz de Paula Gundakar von Colloredo in 1771 married Princess Maria Isabella of Mansfeld and was able to inherit her family's Bohemian estates upon the extinction of the dynasty's male line in 1780, while the original Mansfeld possessions passed to the Prussian Duchy of Magdeburg. The union of the Princely houses of Colloredo and Mansfeld was officially approved by decree of Emperor Joseph II in 1789 and was mediatised to the Austrian Empire in 1806.
After World War II the family was expelled from Czechoslovakia. Parts of the Colloredo's possessions, among them Dobříš Castle, were restored by the Czech Republic to Jerome Colloredo-Mansfeld. A lawsuit over the arts collection at Opočno Castle is pending.
Princes of Colloredo-Mannsfeld (1789–present)
- Franz Gundakar (1789-1807) 
- Rudolf (1807-1843)
- Franz (1843-1852)
- Joseph I (1852-1895)
- Joseph II (1895-1957)
- Joseph III (1957-1990)
- Hieronymus I (1990-1998)
- Hieronymus II (*1949)
- Hieronymus Graf von Colloredo (1732–1812) was Prince-Bishop of Gurk from 1761 and last Prince-Archbishop of Salzburg from 1771 until 1803, when the Archbishopric was secularized.
- Hieronymus Karl Graf von Colloredo-Mansfeld (1775–1822) was an Austrian corps commander during the Napoleonic Wars.