Donald Trump would probably fail the US citizenship test

In case you missed it, Donald Trump embarrassed himself, again.

During an interview, broadcast on SiriusXM, Trump said that Andrew Jackson, the 7th President of the United States, could have stopped the Civil War.

I mean had Andrew Jackson been a little bit later you wouldn't have had the Civil War. He was a very tough person, but he had a big heart,

He was really angry that he saw what was happening with regard to the Civil War, he said, 'There's no reason for this.'

Andrew Jackson died in 1845, 16 years before the outbreak of the US Civil War.

Mr Trump went on to tweet that had he been alive, he 'would never have let it happen'.

Political commentators, historians and the general Twitter populace was quick to jump on Mr Trump's knowledge of American history.

What's particularly interesting however, is the fact that those applying for US Citizenship have to answer questions about the cause of the Civil War...

One of the questions, shared by TIME journalist Ryan Teague Beckwith, asks hopeful American citizens to "Name one problem that led to the civil war".

The answer - just in case you're reading Mr. Trump - is slavery.

More: Donald Trump’s most controversial tweets since becoming president