European equity benchmarks closed higher Monday, led by one of the best daily gains for Germany’s bourse in nearly eight weeks as Chancellor Angela Merkel said she would step down as chairwoman of her conservatives, introducing fresh leadership uncertainty in one of Europe’s most powerful countries. The Stoxx Europe 600 rose 0.9% to close at 355.51. Germany’s DAX 30 shot up 1.2% to end at 11,335.48, representing its best daily gain since Sept. 4, while France’s CAC 40 advanced 0.4% to reach 4,989.35. The U.K.’s FTSE 100 surged 1.3% to finish at 7,026.32, logging its best single-session climb since Sept. 21.

U.S. stock benchmarks ended lower on Monday. The S&P 500 fell 0.7% to around 2,641.25. The Dow Jones Industrial Average shed 1% to close at 24,442.92 ad Nasdaq Composite Index dropped 1.6%, to 7,050.29. Losses accelerated late Monday after a Bloomberg News report surfaced indicating that President Donald Trump’s administration was prepared to impose tariffs on all China’s imports

Germany without Angela Merkel

Chancellor Angela Merkel has been a seemingly invincible figure in German politics. In office 13 years, she has been Europe’s most powerful leader, a presence so synonymous with stability Germans call her Mutti, or Mother. So it was a familiar sight on Monday to see her live on television, until she asked Germans to do something far less familiar, and “get ready for the time after me.”

The chancellor said she would step down as leader of her conservative party in December and would not seek re-election in 2021. That means Ms. Merkel may remain on the political scene for months to come. But few observers believe she could hang on until the end of her term, speculating that new elections could be held as early as next year.

The chancellor’s decision now makes clear that neither she nor her country are immune to the forces that have reordered politics across the Continent — the cratering of the political center; the rise of populist forces; the blowback from the migration crisis; and a redrawing of the political fault lines away from the historical left-right divide toward a battle between liberal pro-European values and their nationalist polar opposite.