Before returning home, Erdogan traveled to the western city of Cologne where several thousand critics turned out to protest everything from Turkey's record on human rights and press freedom to its treatment of minority Kurds.
German Chancellor Angela Merkel, after meeting Erdogan on Friday, said that "deep divisions" existed between the two countries. Construction of one of Europe's largest mosques financed the "Turkish-Islamic Union" (DITIB) - religious organization that controls Ankara. On Saturday in Cologne, the Turkish leader sought to strike a conciliatory note.
Turkish President Recep Tayyip Erdogan is speaking at the inauguration of a mosque under heavy security as he winds up a visit to Germany. The rhetoric escalated to the point where Erdogan called Germany's mainstream parties "enemies of Turkey" and accused German officials of acting like Nazis, prompting Merkel to condemn his comments.
Erdogan said that the United States administration tried to solve issues between the two countries "with the language of threat instead of dialogue".
"As a president, I could not stomach the fact that he was alienated", the Turkish leader told the audience.
"Hate speech against Germany", ran the headline in Saturday's edition of best-selling daily Bild.
The Turkish currency lira saw a sharp plunge after the U.S. implemented trade sanctions. "The Turkish-German relationship is neither better nor simpler after this visit".
In Cologne, a major center of the three million-strong Turkish community in Germany, a few hundred Erdogan supporters gathered behind security barriers waving flags and wearing scarves in Turkey's red-and-white national colors.
"It's a great honor for us", said supporter Ali Tas of Erdogan's visit.
Almost 1,000 people protesting against the move, assembled on the opposite bank of River Rhine, after permission to march from the city centre was denied to them.
Both Cologne Mayor Henriette Reker and the state's premier Armin Laschet declined to attend the mosque ceremony. They were to have held talks at a stately home, but the venue was switched after its owners objected.