President Donald Trump questioned why the American Civil War couldn't have been avoided, according to The Hill, citing an interview on SiriusXM.
Trump claimed that if President Andrew Jackson had served later, the United States would have avoided what is by far the deadliest war in its history.
"He was really angry that he saw what was happening with regard to the Civil War, he said: 'There's no reason for this,'" Trump said during the interview.
Jackson died in 1845, 16 years before the outbreak of the war.
Trump followed up on the interview with a post on Twitter:
Southern US states began seceding from the Union in December 1860, following the election one month earlier of President Abraham Lincoln, whose Republican Party had strong anti-slavery sentiments. The economy of the mostly agricultural South was at that time dependent on massive-scale, slave labour.
Most Southerners were poor and did not own slaves, but the region's politics were largely dominated by a wealthy class of slaveholders.
The Union defeated the Confederacy in 1865 after a war that took more than 600,000 lives. Some estimates put the death toll much higher.