Former businessman Wachtmeister announced earlier this year that he was suffering from cancer.
“Life has different events and challenges. One month ago, my life was fundamentally changed,” the former party leader wrote in a Facebook post in May.
His wife confirmed to newspaper Svenska Dagbladet on Saturday night that he had died.
Wachtmeister had a long history in both the business world and political sphere in Sweden, and became widely known to the public in 1991 when he co-founded the economically liberal, anti-immigration New Democracy party, which gained 6.7 percent of the popular voted in elections the same year.
Along with party co-founder Bert Karlsson, the party’s leading duo became known as “the count and valet”, due to Karlsson's working class background and Wacthmeister's noble ancestry.
New Democracy campaigned on an agenda of reform and restricted immigration, with policies in favour of entrepreneurship and deregulation.
The party also supported Sweden’s 1995 application for European Union membership.
“He was a classic populist politician with a completely unique way of speaking. He was adept at it,” political scientist Andreas Johansson Heinö of conservative thinktank Timbro told TT.
“Ian was a person who visibly thrived in the spotlight. He enjoyed speaking in parliament and brought humour to the debates, something that was unusual at the time,” Heinö said.
“Ian dared take a stand. That’s why I went into politics with him,” Karlsson said.
“He was a fantastic debater,” he added.
Wachtmeister left New Democracy in 1994 after disagreements with the party leadership. In 1998, he unsuccessfully attempted a political comeback by founding the New Party (Det nya partiet), a party with similar ideology to New Democracy, after the latter’s collapse at the 1994 elections.
In recent years, Wachmeister acted as advisor to Jimmie Åkesson, leader of right-wing nationalist party the Sweden Democrats, and appeared as a guest speaker at that party’s convention in 2010.
Prior to forming New Democracy, he published his book Ankdammen, a criticism of Swedish politics that drew heavily on satire.
In his early career, the former businessman worked in the metal industry, including a CEO post at Oxelösunds Järnverks.
“He could talk to just about anyone. Perhaps that is also why he did so well in business,” Karlsson said.
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