She was the daughter of lensmand Laurids Brockenhuus (1552–1604), owner of Egeskov and Bramstrup, and Karen née Skram (1544–1625).

[citation needed] After returning to Denmark in 1597, he managed his estates, included Ulfeldtsholm which he had inherited from his father in 1693.

He was a driving force behind the alliance with the Netherlands in 1621 and the extended union with the duchies of Schleswig-Holstein in 1623.

Unlike the Privy Council, from 1621 he worked for the creation of a Protestant union under the leadership of Christian IV in the Thirty Years' War, an effort which was successful in 1625.

[2] Ulfeldt has left a vivid account of his travels in the Holy Land and Egypt, which is still kept at the Danish Royal Library, describing Constantinople, the Colossus of Rhodes, Islands in the Adriatic Sea, Cyprus, Tripoli, Beirut, Sidon, Tyre (Lebanon), Jaffa, Jerusalem, and Cairo together with the Giza pyramids and Pyramid of Djoser.