Everyone knows that Cardiff is the capital of Wales.

But it is not common knowledge that it only became the capital officially as recently as 1955.

Much before that the capital was Strata Florida Abbey, where Llywelyn the Great held council in 1238, and then Machynlleth, where Owain Glyndwr had his parliament in 1404.

Even Ludlow in Shropshire, between 1473 and 1689, was among the towns to hold the seat of government for Wales.

But a film from the Second World War (which you can watch below) has been unearthed on YouTube which claims that Aberystwyth was much more recently the capital of Wales.

Made in 1943, the official training film shows US soldiers how to behave in Britain.

In one section, the GI Movie for the Army Service Forces shows youngsters in a classroom being taught the different capitals of the countries in the UK.

Edinburgh was named as the capital of Scotland and Belfast for Northern Ireland.

But for Wales, Aberystwyth was identified as the capital of Wales.

Was this just a mistake by the makers of the movie, now watched by more than 800,000 people on YouTube?

Or was Aberystwyth, indeed, once the capital of Wales?