The anti-immigrant group Identity Evropa was behind nearly half of the 478 reports recorded by the A.D.L. Identity Evropa describes itself as “a fraternal organization for people of European heritage located in the United States that participates in community building and civic engagement,” but the A.D.L. classifies it as a white supremacist group and the Southern Poverty Law Center describes it as a white nationalist group.

Far-right groups have increased their activity since President Trump’s election, and white nationalist leaders have been encouraged by how the president has spoken about their behavior. In a report released earlier this year, the Anti-Defamation League found that anti-Semitic episodes had increased 57 percent in 2017 from the year before.

The new report documented racist fliers covering photos of black historical figures outside the University of South Carolina’s African-American studies program, as well as fliers at multiple schools encouraging students to report undocumented immigrants to Immigration and Customs Enforcement.

Mr. Segal said the Anti-Defamation League provides guidance for universities on how to respond to racist or anti-Semitic propaganda on their campuses, a delicate task that can get complicated when the messaging on the posters is not illegal or even contrary to the school’s code of conduct.

At Texas A&M University, Corpus Christi, the administration drew criticism this year from students for its initial response to anti-immigrant fliers posted around campus. Kelly Quintanilla, the university’s president, said in a statement to the campus community that such incidents were the “price we pay for our precious right to freedom of speech,” prompting demands from student activists for the university to investigate and find who was responsible.

Image A flier found this year at Texas A&M’s campus in Corpus Christi. Student activists urged the university to find the people responsible for the flier and others like it. Credit... Daniel Yzaguirre

“We felt it was a threat to our immigrant students,” said Daniel Yzaguirre, a student activist who recently graduated from the university.