In 1961 when he was old enough, Karl von Wendt inherited the extensive estates of his father in Gevelinghausen, Wiggeringhausen in and around Lemgo . Wendt's father, the economist Carl Freiherr von Wendt-Papenhausen, had been killed in Russia during the Second World War.
Karl great passion was motorsport and from 1959 to 1971 he drove karts, rallies, touring cars, sports car and Formula 3. He loved Porsche cars and had an extensive private collection. He formed his own team, and drivers such as Jochen Neerpasch, Helmut Marko, Rolf Stommelen, Willi Kauhsen and Gerhard Mitter all drove for him at one time or another
Among his greatest successes was winning the European Championship as a Porsche works driver in 1967 with a Porsche 911.
His most ambitious project was to built a race track in the Sauerland, where Wendt had already invested a lot of money. When the planned Sauerland-Ring was politically prevented in 1971, he ended his motorsport career and dissolved his racing team.
Apart from motorsport, Karl von Wendt was also a passionate sailor.
Karl had various and varied projects in Germany and Canada ranging from theme parks and organising horse-drawn carriage rides through Hochsauerland to a campsite in Feriendorf with 25 log cabins and a restaurant. He turned his castle into a hotel, which he opened in 1973 and also founded the Tourism Association of Sauerland that year.
Unfortunately many of his business ventures failed and he ended up having to sell large portions of his property, the leisure park and his castle.
In the mid 1980s he emigrated to Canada and started a new business there running a computer company. On February 6, 2006, he died in his Canadian home after a serious illness.