Trump made the comments in a Wall Street Journal interview published Thursday.
The president had planned to hold his first campaign rally since early March in Tulsa, Oklahoma, on June 19. Those plans were changed after the date and location were criticized as insensitive to the country's history of racist violence.
June 19, known as Juneteenth, is an unofficial holiday that celebrates the end of slavery in the United States. It commemorates the day in 1865 when Union soldiers brought word of the Emancipation Proclamation to enslaved people in Texas.
Trump's indoor rally in Tulsa was moved to Saturday instead.
"I did something good: I made Juneteenth very famous," Trump told the newspaper.
Tulsa was also the site of one of most notorious incidents of racist violence in U.S. history. In 1921, a mob of white residents attacked and killed black community members, destroying a thriving black business district.