IF anyone doubted the global interest Scotland's constitutional debate would create, then doubt no more – not after yesterday's press conference in Edinburgh Castle's historic Great Hall.

Fifteen minutes before the starting time, it was standing-room only in the 16th-century building, with journalists having to pick their way carefully though a forest of camera tripods.

Television crews from China, Spain, the US, Scandinavia, Azerbaijan and many other countries arranged themselves around the seats, where 80 journalists sat cheek by jowl – wedding-style, Scots on the right, foreign press on the left – awaiting what one local hack described, with a glance at his surroundings, as "the man who would be king".

And, while they waited for First Minister Alex Salmond, who arrived later than even the most fashionable bride, avid discussions got under way among the 50 foreign journalists in several languages, but particularly Spanish. Such is the interest in the Scottish constitutional debate in Spain, that a football team's worth of Spanish reporters had made the journey north, representing nine different broadcasters and newspapers from Madrid, the Basque country and Catalonia.

Their excitement was palpable, especially that of young Catalan TV reporter Carles Costa. Bundled up in a heavy coat against a Scottish January, and regretting not having eaten lunch before he came, he explained what made the greatest impression on him: that in the UK, it was possible to debate independence in polite terms.

He said: "We can't even have the debate. In Spain, anyone saying they want a referendum is called an extremist."

The majority of people in Catalonia are thought to favour a Catalan version of devo-max, he added, not independence, but what a marvel to be able to talk about it.

"Here, even if the parties in London are not for it, you can have a polite discussion," he said, with a look of something like wonder in his eyes.

Grabbing a coffee in the castle cafe before the press conference, Gunnal Ringheim from Norwegian tabloid Dagbladet noted there was significant and growing interest in the Scottish constitutional debate across the North Sea.

How puzzling to Norwegian eyes, though, that Mr Salmond was so keen to be part of the EU, something Norway has rejected in two referendums. How did he explain that contradiction, Gunnal wondered.

Such new perspectives on the hoary old Scottish constitutional debate made for some refreshing questions when the First Minister finally did arrive. Before he took the stand, however, there was a short film, outlining a blink-and-you'll-miss-it version of Scotland's constitutional journey, from the Declaration of Arbroath to the Clearances in 15 seconds, which left most of the assembled media looking slightly bemused.

Perhaps more significant than the dates was the emotive accompaniment of soaring violins and choral harmony. A sign of tactics to come?

The venue was "rather forced upon us" by size requirements, claimed Mr Salmond before he got to the important stuff, raising a few eyebrows. It was clear he was revelling in one happy coincidence, noting the hall was built during Scotland's 1000-year period of history as an independent country.

Taking questions from the Scottish press and "our international friends", he competed at times with a wailing wind that whipped around the vaulted roof and caused doors to slam at the back.

Don't worry, quipped the First Minister, as a few anxious heads were raised to the ceiling, this hall has stood for 500 years. Quoting Burns and the entertainer Andy Stewart, a relaxed Mr Salmond couldn't resist a joke at David Cameron's expense, offering him elocution lessons should he ever wish to quote Burns again in the House of Commons, a reference to the Prime Minister's attempt earlier in the day that will have left many a primary school teacher blanching in dismay.

As the event drew to a close and journalists peeled off quietly to file copy for deadlines across several timelines, the size of the appetite for Scotland's constitutional debate beyond our borders was clear.

And surely it can only grow between now and 2014.