Bond markets were also flashing warning signals of recession. The gap between U.S. two-year and 10-year Treasury yields - a closely watched metric for signs of a slowdown - fell to less than a basis point after shrinking on Tuesday to its narrowest since June 2007.
The German figures, along with data showing the slowest growth for Chinese industrial output in 17 years stoking recession worries, knocked the wind out the sails for stocks.
Equity investors on Wall Street and Asia had cheered earlier when U.S. President Donald Trump pushed back a Sept. 1 deadline for new tariffs on remaining Chinese imports.
The S&P 500 .SPX , which had fallen 1% on Monday, rose 1.5% overnight, sending Asian stocks outside Japan .MIAPJ0000PUS up 0.6%. Benchmarks in Shanghai, Hong Kong and Tokyo all mirrored the surge in U.S. stocks.
But the momentum ebbed in Europe, as optimism faded that Trump's move meant tensions were easing and Germany's slowdown showed the damage already done by the trade war.
"The trade war and the dispute between U.S. and China has already had an impact - especially when you look at countries most sensitive to global trade like Germany and even Italy," said Christophe Barraud, chief economist and strategist at Market Securities in Paris.
The MSCI world equity index, which tracks shares in 47 countries, was flat.
In another sign the trade dispute is dragging on economic growth, China's industrial output slowed more than expected in July. Its 4.8% growth was the lowest in 17 years.
The Japanese yen, considered a safe haven, gained 0.3% to 106.42 per dollar as the Chinese data signalled that any resolution to the trade war was a long way off.
Mirroring that view, the offshore Chinese yuan fell 0.4% against the dollar to 7.0337, erasing gains made the day before and remaining weaker than the 7 to the dollar it reached last week.
In commodity markets, oil prices fell after the Chinese data from China and a rise in U.S. crude inventories, erasing some of the gains made after Trump's tariff delay.
Brent crude was down 54 cents, or 0.9%, at $60.76 a barrel at 0744 GMT, after rising 4.7% on Tuesday, its biggest percentage gain since December.
(Reporting by Tom Wilson; editing by Larry King) ((T.Wilson@thomsonreuters.com; 44-20-7542-4531; Reuters Messaging: email@example.com))