The Know-Nothings wanted German and Irish immigrants to get out because they were allegedly subversive and diseased people who were stealing American jobs. White preachers and politicians of the 1820s urged freed blacks to move to West Africa, supposedly for their own good.

From that drive to encourage blacks to go back where they came from to waves of nativist attacks on Catholics, Jews, Asians and Hispanics in nearly every generation that followed, “go home” rhetoric is as American as immigration itself.

President Trump’s raw assertion of nativist language, in attacks Sunday and Monday on four Democratic congresswomen — all of them U.S. citizens, three of them native-born — is consistent not only with his long history of attacks on people he perceives as the other, but also with the nation’s oscillating attitudes toward immigration.

From Calvin Coolidge’s warnings in the 1920s that the country was becoming “a dumping ground” and that “America must remain American” to the “America: Love it or leave it” rhetoric that surrounded Richard Nixon’s presidency, the nation’s leaders have struggled for two centuries with ambivalence about its core identity as a magnet for immigrants.

“They have to love our country,” Trump said Monday, doubling down on his initial statement on Twitter that the House members should “go back and help fix the totally broken and crime infested places from which they came.” “These are people that hate our country. . . . They’re free to leave if they want.”

Trump’s comments have been criticized as racist, nationalist, nativist and ignorant, even as some of his supporters have defended his statements as blunt but necessary assertions that new Americans have an obligation to support their adopted country.

There is hardly any ethnic or racial group in the country that hasn’t been told to go back where they came from. In collections of voices from the Japanese American internment camps of the World War II era, in diaries of the earliest Italian and Irish immigrants, in Jewish novels and memoirs from the turn of the 20th century, the slur is a mainstay.

Sometimes, it is a reaction to political protests: “If you don’t like it here, go back where you came from.”

Sometimes, it is a reaction to foreign conflicts, a backlash against people whose ancestral homes — Japan, Korea, Vietnam, Iraq, Afghanistan — has become a battleground for the U.S. military. Asian Americans targeted with such slurs could respond, “We are here because you were there,” suggested Elaine H. Kim, an Asian American studies professor at the University of California at Berkeley.

“ ‘Love it or leave it’ was not necessarily a form of racist exclusion,” said Christian Appy, a historian at the University of Massachusetts at Amherst. “In the 1960s, it meant that wherever the flag stood, you had to support it. But it also had a racial component because Nixon was courting the white, middle-class people who had traditionally voted Democratic.”

Rhetoric that angrily tells fellow Americans to “go home” can be racist, nationalist or both, Appy said. “They overlap and reinforce one another.”

Most historians trace the origins of American anti-immigrant politics to the first big wave of newcomers to the country after the nation’s birth.

“You can’t live under the Trump administration and be a 19th-century historian and not think all the time about the Know-Nothing party,” said Amy Greenberg, a history professor at Penn State University. In 1848, the U.S. population was 17 million and the foreign-born population was 1.7 million. Six years later, the foreign-born population had more than doubled, with most of the immigrants hailing from Ireland and Germany. And most of the newcomers were Catholics, entering a nation that was almost entirely Protestant.

The resulting backlash took the form of a new political party, officially the American Party, better known by its nickname, the Know-Nothings. Its members spouted overtly anti-immigrant rhetoric, including calls for the new arrivals to be put on ships back to their homelands. In the early 1850s, the party won governorships, including ones in Maryland and Maine.

“The big cry was ‘let’s deport immigrants who are criminals,’ ” Greenberg said. “They were really wound up about which Bible to teach in the public schools,” seeing Catholic texts as subverting the King James version.