Bismarck died after injecting cocaine 'every hour for a day'

In the aftermath of the notorious drug-induced death 21 years ago of his friend Olivia Channon, Count Gottfried von Bismarck vowed: "My days of living it up are all over."

The extent to which he failed to keep to his promise was revealed yesterday when a pathologist told an inquest that the count's body had the highest level of cocaine he had ever seen.

The body of the great-great-grandson of imperial Prussia's "Iron Chancellor", Otto Von Bismarck, was found in his near-empty £5m flat in Chelsea, southwest London, in July this year, up to three days after he died from a massive overdose of cocaine and morphine he had injected during a 24-hour drink and drugs binge. An estate agent selling the flat, close to Sloane Square, discovered the body after being asked to check on the count by his father, Prince Ferdinand von Bismarck.

Westminster coroner's court heard that the 44-year-old German socialite was found lying on a mattress with his arm exposed and blackened. He had injected himself every hour for a period of nearly 24 hours before his death.

Professor Sebastien Lucas, who conducted a post-mortem examination, said the amount of cocaine in the count's body was highest he had seen in his career and was accompanied by traces of morphine that could have come from heroin. The inquest heard he also had liver damage from alcohol and drug abuse as well as HIV and hepatitis B and C.

Recording a verdict of death from a heart attack caused by drug dependency and the overdose, the Westminster coroner, Paul Knapman, said: "I think this is a very regrettable story. The reckless behaviour with cocaine has caused his death."

The tragedy was the final act in a life which had begun steeped in privilege and early academic brilliance only to be dogged by psychological frailty and a reputation as a louche hell-raiser. Friends said Von Bismarck had spent much of the last two decades living under the shadow cast by the death of Ms Channon. The 22-year-old daughter of the Conservative cabinet minister Paul Channon, was found in the count's bed in his rooms at Christ Church College, Oxford, after taking a heroin overdose while celebrating the end of her finals in 1986.

Von Bismarck was charged with possessing cocaine, fined and ordered home to the family castle near Hamburg after vowing to live life on the straight and narrow. He was awarded a third-class degree in politics, philosophy and economics. The inquest heard that after a brief business career in the former East Germany where the telecommunications company he worked for went bust owing £105m, the count led a chaotic life in London.

Never shy about his homosexuality after coming out in the 1990s, he was in the headlines again in August 2006 when Anthony Casey fell to his death from the roof terrace of the count's flat during a sex party.

Von Bismarck had come out of rehabilitation before his death but he rapidly fell back into his cocaine habit. Named after a great uncle who was involved in the July 1944 plot to assassinate Hitler and tortured in a concentration camp, Von Bismarck was said to have considered his family name, and the expectation it placed upon him, a burden.