The Real Meaning of Ich Bin ein Berliner - The Atlantic: So he fashioned a new speech on his own. Previously, Kennedy had said that in Roman times, no claim was grander than “I am a citizen of Rome.” For his Berlin speech, he had considered using the German equivalent, “I am a Berliner.”
Moments before taking the stage, during a respite in West Berlin Mayor Willy Brandt’s office, JFK jotted down a few words in Latin and—with a translator’s help—the German version, written phonetically: Ish bin ein Bearleener.
Afterward it would be suggested that Kennedy had got the translation wrong—that by using the article ein before the word Berliner, he had mistakenly called himself a jelly doughnut. In fact, Kennedy was correct.
To state Ich bin Berliner would have suggested being born in Berlin, whereas adding the word ein implied being a Berliner in spirit. His audience understood that he meant to show his solidarity.