Fallon began by discussing Eisenberg’s film A Real Pain, which he both stars in and directed in Poland.
"It was such a great film ... I didn't want it to end, to be honest," said Eisenberg. "I just wanted more adventures."
The host then brought up Eisenberg’s Polish heritage.
The actor described receiving citizenship last week from the Polish president, calling it a "great honor" after an 18-month process.
But the next day, Eisenberg said he saw the "top news was that Poland now requires all males to participate in military training," prompting laughter from the studio audience.
Fallon said: "Well, congratulations and when you're done with military training, please come back to the show and talk to us about your next project."
Polish Prime Minister Donald Tusk announced on March 7 that the government was preparing a mass military training program for adult men.
Officials later clarified the initiative would also include women and be voluntary.
Eisenberg was granted Polish citizenship on March 5 at Poland’s diplomatic mission to the United Nations in New York, during a ceremony attended by President Andrzej Duda.
(jh/gs)
Source: TVN24, Wirtualna Polska