One of Germany's most experienced diplomats had to wait three months this year before Warsaw would approve his appointment as Berlin's ambassador to Poland.
The official acceptance of an envoy by a host government is normally a formality, especially between allies - as well as an event used to highlight neighborliness and friendship. But Arndt Freytag von Loringhoven, one of Germany's most experienced diplomats, hasn't received a warm welcome in the Polish capital.
A begrudging Polish government on September 1 finally issued its acceptance of his selection. However, it could not resist referring once again to the cause of the delayed approval, noting that Poles remain sensitive to the "great unhealed wound" of World War II.
The ostensible objection to the selection of Freytag von Loringhoven, NATO's first chief of intelligence and deputy head of Germany's foreign intelligence agency, as envoy was that his father was a German army officer who served in Adolf Hitler's entourage in the final weeks of the war.
"What is strange for us is that Berlin didn't realize their pick could cause resentment," said a senior Polish official.
For Germans, the objection has been bewildering. Freytag von Loringhoven's father was a career officer, and he wasn't charged subsequently with any war crimes. He went on to become a general in Germany's postwar armed forces.
The spat over Freytag von Loringhoven's appointment is just one of a series of recent ugly disputes partly rooted in the past that has brought German-Polish relations to an alarming low. Poland's ruling nationalist conservative Law and Justice Party, known as PiS, has accused Germany of seeking to recover territory it lost to Poland after 1945, and it has repeatedly declared that Germany should compensate Poland for the damage wrought on the country during World War II, a conflict triggered by Nazi Germany's invasion of Poland.
On the day Poland formally accepted Germany's new ambassador, which happened to be the 81st anniversary of the beginning of the war, a Polish parliamentary commission announced it had finalized the amount of reparations it wants Germany to pay. The number has not been formally disclosed, but Warsaw in the past has estimated wartime damages at around a trillion euros.
Poland's prime minister Mateusz Morawiecki says Poland lost 6 million people in the war and "many more than any other country that has received vast reparations ... The Germans razed to the ground over a thousand Polish villages," he said in a recent interview.
Germany has repeatedly denied it owes Poland money after Warsaw waived all war reparations in 1953.
For Germans, the reappearance of wartime history is frustrating. They believe they have accepted moral responsibility for the war and have done much to atone for the past as well as to shape a new peaceful Germany that has helped build the European Union.
They see the PiS as seeking to whip up anti-German feeling solely for domestic political reasons - it plays well to the party's core supporters in the poorer eastern half the country and may have helped the PiS-aligned Andrzej Duda win reelection in a tight presidential race in July.
The main Polish opposition parties agree.
Not only Poland
However, it isn't just relations between Berlin and Warsaw that are being affected by war memories, or what Germans see as their weaponization.
Beneath the surface, war-tied resentments are bubbling in other parts of Europe, too, with possible important ramifications for the consolidation of the EU, a bloc founded partly to ensure European nations would cease squabbling and to avert the chance of any future conflict emerging among them.
Pollsters have noted a rise in anti-German sentiment in the southern European states of Italy and Spain, and in Greece, where the country's post-2008 debt crisis and Germany's handling of it still grates. In Hungary and elsewhere in Central Europe, as well as Italy, German Chancellor Angela Merkel is blamed for encouraging the 2015 migrant influx into Europe with her open-door policy for asylum-seekers.
Some observers predict resentment toward Germany will only grow in the coming months for two main reasons.
The first is that poorer European nations will become ever more frustrated with a widening gap between their economic performance and Germany's, which is likely to weather the economic impact of the coronavirus pandemic better.
"The EU is supposed to be a convergence machine, spreading prosperity rather than embedding differences between rich and poor countries," The Economist magazine noted recently. "It has not worked out that way," it added.
That uneven economic recovery risks fueling populist nationalist anger in the countries that lose out, a possible development Merkel has noted is a risk. In June she backed an EU economic recovery fund, arguing it would serve as "a political instrument against populists and radicals."
The second is that Germany is increasingly becoming the undisputed dominant political force on the European stage, thanks to its economic clout and partly as a result of Britain's exit from the EU, say analysts. Many of the key posts in Brussels are held by Germans, including the presidency of the European Commission, and no major proposal can be adopted by the EU without Berlin's approval.