Johnson himself said he was “excited” to take up the new role on Wednesday, which will involve travelling the globe and meeting foreign leaders as the UK’s most senior diplomat.
However, his track record when it comes to interacting with other cultures is patchy to say the least, and politicians around the world have been slightly less than excited by the prospect of working with a man who once wrote a poem about the Turkish president having sex with a goat.
Angela Eagle, a British Labour MP who is challenging Jeremy Corbyn for leadership of the opposition party, led global bemusement with a stunned reaction on Wednesday that said without words what many were thinking.
Further afield in America, the official reaction was one of carefully restrained laughter.
When state department spokesman Mark Toner heard the news, he struggled to keep a straight face – a broad smile breaking out more than once – before saying the US “looked forward” to working with Johnson.
Toner was not alone in his bemusement. American political scientist Ian Bremmer hoped it might all be an elaborate joke.
In Germany, the hashtag #Außenminister (foreign minister) captured the national mood.
This tweet portrays the “unfiltered emotional response”:
But not everyone saw the funny side. Sweden’s former prime minister was among those despairing over the decision.
And Cher was, well, not happy.
New Zealand crime writer Val McDermid was similarly unimpressed.
The world’s second largest economy was scratching its head as it woke up to the news that Boris Johnson - or “Bao Li Si” as he is known in Chinese - had been made foreign secretary.
“What’s going on?” one baffled Chinese commentator wrote on a popular WeChat group dedicated to life in Britain.
“Foreign secretary Boris is going to hog the global headlines,” the writer predicted, adding: “Does Auntie May think he is a mascot? I can hardly bear to watch it unfold on [state broadcaster] CCTV.”
Weibo, China’s answer to Twitter, also erupted in a bout of Borisology, with many observers focusing on the former London mayor’s hair rather than his foreign policy experience.
“Just from looking at Boris Johnson you can tell that British hairdressing is not doing so well,” quipped one. “He’s so funny!” celebrated another.
Not all observers in China, where Johnson is seen more as a celebrity than a politicalactor, were so enthusiastic.
“What are they doing?” one critic of Theresa May’s selection asked on Weibo. “Boris will be in charge of diplomacy???”
There was also bewilderment at Johnson’s appointment in Beijing’s diplomatic circles.
During his last trip to China in 2013, the loquacious London mayor bamboozled Chinese interpreters with his use of words such as polymorphous and joked about his Bullingdon Club days to a senior Communist party leader.
“The idea of having Boris Johnson as foreign secretary never even entered my mind,” admitted one senior western diplomat.
The diplomat, who keeps one eye on Westminster politics, described Johnson’s appointment as a risky move that had the potential to backfire badly. “But sometimes a bit of charisma helps give you more visibility. Let’s see if he is more pragmatic and less of a performer in his new job.”
In the hours after Johnson’s unveiling, British residents of the Chinese capital were bombarded with sarcastic messages from fellow expats.
“What is happening to your country?” read one provocation sent to the Guardian.
Another, less diplomatic dispatch sent to a functionary of the British embassy said simply: “Your new boss is a plonker.”
Some, however, believe Johnson is the right man for the job.
Among his fans is the former Australian prime minister, Tony Abbott - who once threatened to “shirtfront” Vladimir Putin.
Additional reporting by Christy Yao
This article was written by Bonnie Malkin and Tom Phillips in Beijing, for theguardian.com on Thursday 14th July 2016 04.36 Europe/Londonguardian.co.uk © Guardian News and Media Limited 2010