Adolf Merckle’s apparent suicide could not be a more dramatic manifestation of the anguish that the German billionaire industrialist felt as his business empire seemed about to crumble.

Over four decades the 74-year-old had built one of Germany’s biggest fortunes and controlled a network of about 120 companies that employed more than 100,000 people. But in just a few months, his grip on this empire loosened alarmingly, with Merckle undone by some of the risk-taking spirit that had helped him amass his fortune, estimated at more than $9bn.