President Donald Trump on Friday proclaimed May 1, 2017 as “Loyalty Day.”

He dedicated the day to “recognize and reaffirm our allegiance to the principles upon which our Nation is built.” He named principles like individual liberties, limited government, and “the inherent dignity of every human being.”

Trump also praised members of the U.S. military “from the American Revolution to the present day.” Their loyalty “has made the world a safer, more free, and more just place.”

The president called on government buildings to display American flags. He encouraged others to hold “appropriate ceremonies” and say the Pledge of Allegiance.

Loyalty Day

Loyalty Day was first observed as “Americanization Day” in 1921, in response to rise of communism in Russia. Congress made it an annual observance in 1958. A 1998 revision of the law described it as “a special day for the reaffirmation of loyalty to the United States and for the recognition of the heritage of American freedom.”

It was set for May 1 in order to counter the International Workers Day, originally a socialist initiative. “May Day,” as it’s usually called, is often marked with marches and protests. On Monday many U.S. May Day rallies focused on protesting Trump’s immigration policies, NPR reported.