BERLIN — Barely an hour after Chancellor Angela Merkel watched her efforts to form a broad coalition government fall apart, she retreated to a private room with two dozen conservative allies. Four weeks of intense talks had just ended, with three deadlines missed. The mood was somber. One of her colleagues stood up to thank her, initiating a standing ovation.

It was a polite gesture to mark the end of a polite era. But German politics is now poised to enter a more raucous phase.

The breakdown of the coalition talks last weekend has done more than dent Ms. Merkel’s seeming invulnerability and raise the prospect of new elections, analysts say. Although the Social Democrats agreed on Friday to meet with the chancellor’s party next week — raising hopes for, if not a coalition, then a tolerated minority government — the current situation may well signal the breakdown of Germany’s postwar tradition of consensus and the dawn of a messy and potentially unnerving politics.

“The distinctive political tradition of the Federal Republic of Germany is change through consensus,” said Timothy Garton Ash, a professor of European studies at the University of Oxford. That was what was at stake, he said. “It hasn’t worked so far this time.”