CHICAGO — It was supposed to be a triumphant homecoming for President Obama, and a chance to cast his executive action on immigration as the latest chapter in America’s history of welcoming foreigners.

But the president was forced Tuesday to pare down a speech aimed at selling his immigration plan by protesters who repeatedly interrupted him to demand even more relief.

“I understand why you might have yelled at me a month ago,” Mr. Obama told three women in the audience who stood up to shout slogans of “Not one more!” “Stop deportations!” and “There is no justice!”

“It doesn’t make much sense to yell at me right now,” he said.

The episode emphasized the president’s difficulties just days after he announced that he was taking long-promised unilateral action to protect about five million unauthorized immigrants from deportation. It is sweeping enough that many Republicans have pledged to block it but narrow enough that some immigration activists are demanding more.