More broadly, the gesture came to symbolise Ostpolitik, Brandt's ultimately successful policy of diplomatically reconciling West Germany with its eastern neighbours following the Holocaust and the Second World War.
He remained silently in that position for a short time (about 30 seconds), surrounded by a large group of dignitaries and press photographers.
Both actions attracted controversy within Germany, as did Ostpolitik in general, which was supported by only a narrow majority of the people and had opposition within Brandt's own Social Democratic Party.
Its voters had included a significant proportion of expellees from the formerly-German territories in Poland, most of whom left to support the conservative parties.
While at the time, positive reactions may have been limited, his show of humility was a small but vital step in bridging the gaps World War II had left between Germany and Eastern Europe.
He later noted that: Egon Bahr, an eyewitness and Brandt's friend and political ally of many years, recalled in a 2010 interview: "The only thing he said was that at that moment facing the ribbon, he thought: Just laying the wreath is not enough.
Willy Brandt wrote about that in his memoirs Erinnerungen (reminiscences): Egon Bahr said in his reminiscence Zu meiner Zeit (Back in my time) 1966: Walter Scheel wrote a letter to the news magazine Solinger Tageblatt in 2010 stating: On December 7, 2010, the federal president Christian Wulff and the Polish president Bronislaw Komorowski, on its fortieth anniversary, held speeches about the meaning of this Kniefall for the Polish-German reconciliation.