Oscar Lewisohn
SG Warburg executive and keeper of the founders’ flame
OSCAR LEWISOHN, who has died aged 85, was deputy chairman of the merchant banking house of SG Warburg & Co – and a guardian of the distinctive ethos created by its founders, Sir Siegmund Warburg and Henry Grunfeld.
It was as Grunfeld’s son-in-law that the Danishborn Lewisohn joined Warburgs in its foreign exchange department in 1962. He specialised first in the trading side of the business, helping to build its leading position in the fast-growing Eurobond market, and later in investment management, becoming an executive director in 1969 and serving as deputy chairman from 1987 to 1994.
Throughout his career, Lewisohn adhered to the demanding standards of Warburg and Grunfeld, émigrés from Germany who had established their business in London in 1934 on the basis of meticulous attention to detail, strong client relationships, and caution in risk-taking. But he also admired what he described as Siegmund Warburg’s “forward-looking and dynamic” embrace of new ideas and market developments – and shared his wider interest in the European political scene.
If Lewisohn was a less prominent City player than other protégés of the founding partners – such as (Sir) David Scholey, who became chairman of Warburgs – he was recognised as a keeper of their flame. Scholey called him “a very fine person of great integrity” who attracted “deep respect, loyalty and affection” within the firm.
Oscar Max Lewisohn was born in Copenhagen on May 6 1938, the youngest of four children of Max Lewisohn, director of a business supplying materials for duvets and eiderdowns, and his wife Jenny, née Cunild. Like most Danish Jewish families, the Lewisohns fled to Sweden in 1943 to avoid Nazi persecution.
Returning after the war, Oscar completed his education at Copenhagen’s Sortedam Gymnasium and started work with a company trading in grain and other food products. He was a trainee with the investment bank R Henriques before his marriage in 1962 to Louisa Grunfeld, whom he had met on a cruise to Israel. An invitation followed from Siegmund Warburg to join the London firm “for a year or so” to see how he got on; he stayed for 33 years.
Lewisohn was proud of Warburgs’ transition, in the vanguard of the City’s Big Bang reforms of the mid1980s, into a full-scale securities trading operation. As part of that reorganisation, he moved from the bank to its investment management affiliate, Mercury Asset Management, overseeing its Swiss connections and advising some of its Scandinavian clients.
After MAM was taken over in 1995, Lewisohn left to join Soditic, a London-based private investment group founded by his friend Maurice Dwek, remaining as chairman until last year.
Cultured, gregarious and multilingual, he thought of himself as a European, and was deeply disappointed by Brexit. He was prominent in Anglo-danish relations, including the Danish-uk Chamber of Commerce, and was appointed a knight of the Danish Order of the Dannebrog in 1992. He was known in his family as “the great connector” of distant relations across Europe and America.
With his second wife Margaret he converted an indoor swimming pool at their Wimbledon home into a hall for recitals by young musicians under the banner of the Marryat Players. He was a director of the Yehudi Menuhin School and the Peasmarsh Chamber Music Festival Trust in Sussex.
He supported cancer charities in memory of his first wife and advised on the 2002 merger of the Cancer Research Campaign and the Imperial Cancer Research Fund.
After Louisa’s death in 1985 he married secondly, in 1987, Margaret Paterson, who survives him with their two daughters, and three sons and a daughter of the first marriage.