Wim Duisenberg, the former head of the European Central Bank, has been found dead in a pool at his villa in south-east France, French police say.
Wim Duisenberg enjoyed strong German backing for the ECB job
He drowned following cardiac problems at his home in the town of Faucon, a regional prosecutor says.
The former Dutch finance minister was the ECB's first president, and oversaw the introduction of the single European currency, the euro.
The 70-year-old had stepped down in 2003 after five years in the job.
Under Mr Duisenberg, the euro evolved from being only a market-traded currency into coins and notes in the pockets of 300 million people in 12 European countries.
Current ECB President Jean-Claude Trichet called the death a "terrible loss".
Born in 1935, Mr Duisenberg worked for the International Monetary Fund before serving as his country's finance minister from 1973 and 1977.
A member of the Dutch Labour Party, his views on responsible economic management changed. Later in life, he preferred strong fiscal discipline rather than a strategy of promoting growth through major public spending.
Germany and France - the two biggest eurozone economies - wrangled over Mr Duisenberg's appointment in 1998, and over who should succeed him.
Mr Duisenberg became first ECB president with strong German backing - with Mr Trichet being named as his successor at the same time as part of a Franco-German deal to share power.
The shift to euro notes and coins took place on 1 January 2002, and was feted with firework displays and street parties in some European cities.
The ECB cut interest rates in the euro countries to their lowest level since the World War II under Mr Duisenberg.
But critics said the slowdown in the eurozone would not have been so severe if he had cut rates sooner and more aggressively.