In the living room of his two-story stucco house, Klaus Kretschmer's eyes welled up as he spoke about a German border — and not the one crossed by refugees whose arrival since 2015 has driven him to far-right politics. 

Kretschmer, 66, faltered in discussing an internal frontier, torn down almost three decades ago. He had been drafted to serve at the Berlin Wall, he said, declining to say more about what he had done there. Border troops used violence in keeping fellow citizens from liberating themselves.

Few eastern German towns are as remote from the capital as Oppach, a hamlet that hugs the border with the Czech Republic. But the wall that once split Berlin remains unspeakable for Kretschmer, who still lives under the shadow the socialist dictatorship cast over the eastern half of the country.

That shadow became a fault line in the Sunday election that propelled a far-right party into the national Parliament for the first time in almost six decades. The nationalist, anti-immigrant Alternative for Germany, or AfD, was the second-strongest party in the former communist east, where it captured 21.5 percent of the vote compared with 12.6 percent nationwide and 10.7 percent in the west. It displaced Die Linke, a far-left party with origins in the East German Communist Party, as the east's main alternative to the ­center-right block led by Angela Merkel, who claimed a fourth term as chancellor.

Oppach, whose population is graying if not white-haired and includes few people of migrant background, is a case study in the appeal of the AfD, which claimed 46 percent of the vote here. In particular the town reveals why memory of the socialist state, and its quick absorption into the federal republic, makes the east more fertile ground for right-wing populism than its western counterpart. It therefore offers one way of understanding why a country scarred by political extremism still would prove susceptible to far-right politics, as a party that promises "Islam does not belong to Germany" prepares to become the third-largest faction in Parliament.

"Islam was imposed on us," said Kretschmer, echoing the party's stance and claiming that Arab migrants are treated better than ethnic Germans. "The refugees can come here with 10 children, and they get everything for free." 

Winding his Mercedes-Benz through roads cut into the hills of Saxony, the lone German state where the AfD emerged on top, he acknowledged that he is not worse off because of the influx of asylum seekers, mostly Syrians fleeing the civil war. "But I could be doing better," said Kretschmer, who used to vote for the pro-business Free Democrats because he "wanted German money to stay in Germany."

The feeling of being shortchanged is familiar to him. It recalls his experience after the wall came down in 1989. 

"Everything broke down," Kretschmer said. "The youth left, and many elderly people couldn't find work."

He lost his job in a factory producing electronic control systems and, after retraining, went to work as a construction manager. When his wife retires next year from her job as an accountant, he said, "she won't even get the minimum pension."

"People in the west do better," he said. 

This is true but no longer by every measure, and it denies the scale of investment that has helped narrow a yawning gap between the two halves of the country, said Reiner Klingholz, director of the Berlin Institute for Population and Development.

The equivalent of $1.89 trillion of West German money went into rebuilding the east after reunification. 

"Nowhere in Germany has life improved so much as in the east," Klingholz said. "But this is not how people feel. Instead they're frustrated because there's more uncertainty."

Uwe Wockartz, a janitor buying his lunch in Oppach's tiny commercial center on a recent weekday, said the promise of economic uplift made by Helmut Kohl, the conservative chancellor and architect of reunification, had gone unfulfilled. Today's leaders have failed similarly, he said. 

"They've forgotten their own people," said Wockartz, 60. 

There are reasons to be dissatisfied, said Steffi Grosskreutz, a pharmaceutical technician. Many residents can find only short-term work contracts. Companies follow lower costs across the border to the Czech Republic or Poland, she said.

But Grosskreutz, 37, said she had no reason to think the AfD would fix these problems.

"The AfD makes many promises, but they don't have a real concept," she said as she loaded groceries into her car at Aldi, a discount supermarket chain. She voted for Die Linke and the Greens. 

Also voting for Die Linke — as a "protest vote" but in support of the left — was Michael Klöpper, a teacher. He said jealousy and insecurity — ingrained rather than eradicated by reunification — has inspired "hate for foreigners." Polling in 2015, when public opinion was still more favorable to Merkel's decision not to close the borders to asylum seekers, suggested that 46 percent of people in eastern Germany were afraid of the large number of refugees arriving in the country, compared with 36 percent in the west.

Amplifying fear in the east are limited horizons in small towns where most young people leave and the elderly rarely travel, said Hartmut Elsenhans, a political scientist at the University of Leipzig. He said Saxony is historically insular. Because of poor television signals, he said, "people in Saxony were not connected to debates happening in West Germany."

But that did not stop Saxony from being the birthplace of famous "Monday demonstrations" demanding democratic rights two months before the Berlin Wall came down. 

The chant with which East Germans took to the streets, "Wir sind das Volk" ("We are the people"), is today freighted with new meaning. It is the cry of Pegida, the anti-Islam movement founded in Dresden in 2014, whose members favor Mondays for their demonstrations.