The newly-appointed chief was part of a delegation from the German FA that visited Gdansk on Wednesday to observe the Westerplatte memorial, site of the first shots fired in the second World War.
"This place tells a terrible chapter in our history and is a clear reminder to us that something like this should never happen again," Niersbach told Goal.com, lamenting the "incomprehensible suffering" Germany had "brought on this wonderful country".
"We are very grateful that we are back on such friendly terms with Poland, and we consider it our obligation to always and forever stand in support of peaceful co-existence."
|"This place tells a terrible chapter in our history and is a clear reminder to us that something like this should never happen again"
Without a word, the delegation observed the remains of the peninsula's munitions depot, which to this day remains untouched, riddled with bullet holes from the war.
A guide from Poland recounted the history of the battle, which began as the German ship Schleswig-Holstein opened fire on the Polish garrison. The outnumbered Polish forces held off the German attack for seven days before surrendering.
After the history recountal, the German delegation continued to a hill overlooking the Baltic sea, at the top of which stands a 23-metre granite memorial. The monument was erected in 1966 to commemorate the coastal defenders, and faces a sign that reads: "Never again war".
En route, several Polish school children visiting the memorial bid the visitors "Guten tag", a testament to the improvement of relations between Poland and Germany since the war.
Once at the monument, Niersbach placed a wreath, with a ribbon reading "In honourable remembrance, Deutscher Fussball Bund" at its base, and only then did he break his silence.
After delivering his statement, Niersbach and the delegation quietly left as rain broke out on the hallowed ground.