ULFELDT, KORFITS (1606–1664), Danish statesman, was the son of the chancellor Jacob Ulfeldt. After a careful education abroad he returned to Denmark in 1629 and quickly won the favour of Christian IV. In 1634 he was made a Knight of the Elephant, in 1636 became councillor of state, in 1637 governor of Copenhagen, and in 1643 lord treasurer. In 1637 he married the king's daughter Leonora Christina, who had been betrothed to him from her ninth year. Ulfeldt was the most striking personality at the Danish court in all superficial accomplishments, but his character was marked by ambition, avarice and absolute lack of honour or conscience. He was largely responsible for the disasters of the Swedish war of 1643–45, and when the treaty of Brömsebro was signed there was a violent scene between him and the king, though Ulfeldt's resignation was not accepted. In December 1646 he was sent as ambassador extraordinary to the Hague, but the results of his embassy by no means corresponded to its costliness, and when he returned to Denmark in July 1647 he found the king profoundly irritated. Ulfeldt, supported by the Raad and the nobility, who objected to Christian's fiscal policy, resisted his father-in-law, and triumphed completely. As lord high steward he was the virtual ruler of Denmark during the two months which elapsed between the death of Christian IV. and the election of Frederick III. (July 6, 1648); but the new king was by no means disposed to tolerate the outrageous usurpations of Ulfeldt and his wife, and this antagonism was still further complicated by allegations of a plot (ultimately proved to be false, but believed at the time to be true) on the part of Dina Winhavers, a former mistress of Ulfeldt, to poison the royal family. Dina was. convicted of perjury and executed, but Ulfeldt no longer felt secure at Copenhagen, and on the day after the execution he secretly quitted Denmark (July 14, 1651), with his family. After living for a time in concealment at Amsterdam, he migrated to Barth in Swedish Pomerania, and began the intrigues which have branded his name with infamy. In July 1657 he eagerly responded to the invitation of Charles X. of Sweden, when he invaded Denmark, and entered the service of his country's deadliest foe, for the express purpose of humiliating his sovereign and enriching himself. He persuaded the commandant of Nakskov, the one fortress of Laaland, to surrender to Charles X., and did his best to convince his countrymen that resistance was useless. Finally, as one of the Swedish negotiators at thecongress of Taastrup, he was instrumental in humiliating his native land as she had never been humiliated before. Ulfeldt's treason was rewarded by Charles X. of Sweden with the countship of Solvitsburg in Blekinge; but the discontented renegade began intriguing against his new master, and in May 1659 was condemned to death. The Swedish regents, on the 7th of July, amnestied him, and he returned to Copenhagen to try to make his peace with his lawful sovereign, who promptly imprisoned him and his wife. In the summer of 1660 they were conveyed to Hammershus in Bornholm, as prisoners of state. Their captivity was severe to brutality; and they were only released (in September 1661) on the most degrading conditions. The fallen magnate henceforth dreamed of nothing but revenge, and in the course of 1662, during his residence at Bruges, he offered the Danish crown to the elector of Brandenburg, proposing to raise a rebellion in Denmark for that purpose. Frederick William betrayed Ulfeldt's treason to Frederick III., and the Danish government at once impeached the traitor; on the 24th of July 1663 he and his children were degraded, his property was confiscated, and he was condemned to be beheaded and quartered. He escaped from the country, but the sentence was actually carried out on his effigy; and a pillory was erected on the ruins of his mansion at Copenhagen. He died at Basel, in February 1664.
See Julius Albert Fridericia, Adelsvaeldens sidste dage (Copenhagen, 1894); Danmarks riges historie, vol. iv. (Copenhagen, 1897–1905) ; Robert Nisbet Bain, Scandinavia, chs. vii., ix., x. (Cambridge, 1905).