Danneskiold-Samsøe is a Danish family of high nobility, formerly holding the island of Samsø as a fief. The family uses a traditional spelling of the name; a modern spelling would be Danneskjold-Samsø.
The name was created for several illegitimate descendants of Dano-Norwegian monarchs of the House of Oldenburg. The first grantees were children from the 1677 marriage between Countess Antoinette of Aldenburg-Knyphausen and Ulrik Frederik Gyldenløve, Count of Laurvig, a celebrated (Norwegian) general and the son of Frederick III of Denmark-Norway by his mistress Margrethe Pape, because that marriage was so high for a bastard that King Christian V, the count's half-brother, agreed to guarantee a comital title to all its male-line descendants.
The next grantees were all the children of Christian Gyldenløve, Count of Samsø and eldest son of Christian V himself by his mistress Sophie Amalie Moth, to reward him for his (first) 1696 marriage with his cousin, countess Charlotte Danneskiold-Samsøe, one of the recipients of the previous grant. The male Danneskiold-Laurvigen line was extinguished in 1783, and the Laurvig countship was inherited through the female heiress by the Ahlefeldt family, of the Danish high nobility. In 1786, François Xavier Joseph Gyldenløve, second Count of Løvendal, great-grandson of Count Ulrik Frederik's first marriage, was granted the surname Danneskiold as well [1]; but this line of Danneskiold-Løvendal, too, was extinguished in its male line upon the death of his childless son in 1829. The first marriage of count Christian produced only daughters, but the issue of his second marriage, succeeding to the countship of Samsø, continues in male line to our day and bears the surname in the form "Danneskiold-Samsøe".
Thus, all Danneskiolds since 1829 have been descendants of the eldest son of the relationship between King Christian V and his mistress Sofie Amalie Moth (1654-1719), whom the king elevated to be the first Lensgrevinde til Samsø ("Enfeoffed Countess of Samsø"). Her children carried the surname Gyldenløve and married into other noble families. The eldest son was Christian Gyldenløve (1674-1703), Count of Samsø, who married Countess Charlotte Amalie Danneskiold, a daughter of that other illegitimate branch of Oldenburg kings, as his first wife. However, Count Christian's male line continued from the sons of his second marriage, who however were given the Danneskiold surname, which ultimately prevented its disappearance from among the Danish nobility. One of the true descendants of the original Danneskiold family was Christian Gyldenløve's and his first wife Charlotte Amalie's daughter Frederikke Louise, Countess Danneskiold-Samsøe (1699-1744), who married her kinsman Christian August, Duke of Augustenburg (1696-1754), a "royal duke", and from whose marriage all the future Augustenborgs descend.
The present comital family number the noble families Ahlefeldt, Frijs-Frijsenborg, Kaas, Trolle, Thott, Ulfstand, Ulfeldt, Huitfeldt, Sehested, Gyldenstierne, Rosenkrantz, Rantzau, Reventlow, Brahe, Ruud, Grubbe, Gabel, Krag to Juellund, and Krag-Juel-Vind-Frijs among their ancestress-linked relatives.