“You are changing history,” Donald Trump said on Tuesday of efforts to remove Confederate monuments in Charlottesville, Virginia, and elsewhere across the United States. “You’re changing culture.”

History about as old as the George W Bush presidency, it turns out in a surprising number of cases – and culture stretching back to the heyday of Britney Spears.

Thirty-two Confederate memorials have been dedicated in the past 17 years, according to a survey by the Southern Poverty Law Center (SPLC). That’s at least 135 years after the demise of the secessionist movement the monuments ostensibly celebrate.

The symbols include public schools, plaques and monuments, such as a stone in St Cloud, Florida, engraved in honor of Confederate soldiers and of Florida’s cattlemen and farmers “who risked their lives and fortunes to supply our troops fighting in defense of their families, state and nation”.

Iowa, a Union state, has three Confederate monuments, all dedicated after 2000.

The main monument there comprises three plaques on as many large rocks in Bloomfield, the northernmost point the Confederate army reached in the state. A Confederate lieutenant led 12 armed rangers there, dressed as Union soldiers, on a raid that killed three local people.

A monument in Bloomfield, Iowa, memorializes a Confederate raid. Photograph: http://www.iowacivilwarmonuments.com/

In total, there are about 1,500 symbols of the Confederacy in public spaces, according to the SPLC, which attempted to catalogue them all in 2016.

The symbols vary: 718 are monuments, while 109 are public schools named for Confederate leaders. A quarter of those schools have student populations that are majority black. Ten of the schools have student bodies that are 90% African American.

Not all of the post-2000 monuments are new. Some were dedicated again, including a statue for the Confederate navy officer Raphael Semmes in Mobile, Alabama. It was rededicated in 2000 – 100 years after it was first dedicated – with a memorial plaque and ceremony featuring Confederate flags; red, white and blue balloons; and a cannon salute.

A statue for the Confederate navy officer Raphael Semmes in Mobile, Alabama, was rededicated in 2000. Photograph: Alamy Stock Photo

The most recent efforts to dedicate and rededicate Confederate monuments come amid decades-long efforts to remove them.

In 1994, the National Association for the Advancement of Colored People (NAACP) led an effort to ban Confederate flags from South Carolina, including one that flew over the state house. In 2000, 50,000 people turned out to protest the state house flag. It finally came down in June 2015 after the killing of nine black people in a church in Charleston.

While some of the newer monuments are simple stones or plaques commemorating Confederate soldiers, others are large sculptures celebrating major Confederate leaders.

In 2009, Waverly, Missouri, dedicated a new bronze statue to Gen Joseph O Shelby, who was born to one of the wealthiest families in Kentucky and owned a 700-acre plantation worked by slaves. At the end of the war, he refused to surrender and traveled instead to Mexico, leading 1,000 men to a colony for ex-Confederates. He eventually returned to his home in Missouri.

The murders in Charleston set off a renewed effort to remove the memorials across the country, including a statue of Confederate Gen Robert E Lee that was dedicated in 1924 in Charlottesville.

Trump has been criticized by fellow Republicans, business leaders, military generals and a multitude of Americans for endorsing and spreading the explanation of white supremacists that a rally last Friday in Charlottesville was to defend the statue. The rally became a showcase for Nazi ideology and racist ideology – and then the scene of a murderous attack and a latter-day tragedy.