Is Frans Hals the greatest portrait painter of the 17th century? His Spanish contemporary Velázquez has a stronger claim to that contested title. His fellow Dutchman Rembrandt is a more conventional choice. However, Hals has something these greater artists lack, something that makes him a tonic for our troubled times. Velázquez is more powerful, and Rembrandt is more perceptive, but what makes Hals unique is his terrific sense of fun.

Feasting on this joyful display at London’s National Gallery (the first major Frans Hals show since the Royal Academy’s retrospective in 1989) you realise that, compared to Hals, most portraitists tend to be pretty glum. Rembrandt and Velázquez were masters of psychological insight. What they couldn’t do half as well as Hals was to show people having a damn good time.

Throughout his long career, Frans Hals’ fundamental theme was happiness. In virtually every painting, you see people smiling, laughing, joking. Such joie de vivre is surprisingly rare. Seeing it here, in such abundance, you wonder why other artists neglect it. The main reason, I suspect, is because it’s so hard to get it right. As in virtually every artform, it’s easier to be earnest than it is to be frivolous, and so most portrait painters are terribly po-faced.

Like an out-of-focus photo, the result is remarkably modern

Not Hals. Even when his subjects aren’t grinning from ear to ear, there’s usually a twinkle in their eye, as if they’re sharing some saucy gossip with the artist. Hals was clearly highly skilled at putting his sitters at their ease. His portraits are like contemporary snapshots, catching the subject in an informal pose, an unguarded moment that reveals their truer nature. His work is strangely reminiscent of the portrait photographs of David Bailey.

How did he manage it? He had the good luck to live through the so-called “Golden Age” of the Netherlands, when the Dutch Republic reached its economic and cultural peak. This gave him a market for his paintings, folk with money to spare and an appetite for fine art. Crucially, his patrons were self-made men, more open to his casual style of portraiture than the stiff aristocratic clients he would have had to court elsewhere.

Unlike Rembrandt, who went to Amsterdam in search of fame and fortune, Hals stayed in his hometown, Haarlem, throughout his life. After his birth in Antwerp, his parents brought him there in 1585, when he was a toddler. He remained until his death, in 1666. Haarlem was a lively, wealthy city, big enough and rich enough to support an ambitious artist, but a lot more intimate than Amsterdam. Hals counted many of his sitters amongst his friends.

We know relatively little about his life, but it seems he had just the right amount of success. Rubens and Van Dyck became superstars and were whisked away to foreign courts. Rembrandt endured a roller-coaster rise and fall. Hals made a steady living, painting people a lot like him.

Character also played a part. An early self-portrait shows a handsome man with a wry smile and a penetrating gaze. His biographer, Arnold Houbraken, depicted him as rather dissolute, “filled to the throat with drink every night”, but this was probably hyperbole. Hals liked a drink, but so did most of his acquaintances. The inn was an important forum for his trade.

The biggest factor was his natural, god-given talent. He worked swiftly, instinctively, painting straight onto the canvas without any preliminary sketching. His spontaneous technique was relaxed but also extremely accurate. Théophile Thoré, the influential French art critic who rediscovered Hals in the 19th century, likened his fluid brushwork to a fencer wielding a sabre. His faces are painted in fine detail, his bodies in a blur of movement. Like an out-of-focus photo, the result is intensely personal and remarkably modern. His later portraits could almost be mistaken for Manet. You can understand why he inspired Whistler and Van Gogh.

Beside the bravura of these starker studies, Hals’ most famous painting, The Laughing Cavalier, seems relatively staid. Neither laughing nor a cavalier (it only acquired its misleading moniker after it entered an English collection in the 19th century), it’s actually one of his tamer, more conventional portraits. Yet it’s such an iconic picture that it’s still a thrill to see it here, in context, alongside his other paintings. It’s the first time it has left the Wallace Collection since it arrived in Manchester Square, well over a century ago.

An even bigger treat is seeing several of his huge group portraits (the first time some of them have left Haarlem since he painted them) and a couple of his pendants: dual portraits of husbands and wives, long since separated, now briefly reunited after centuries apart. After London, this show moves on to Amsterdam in the spring, and then to Berlin next summer. These paintings rarely travel. The last comparable show was over 30 years ago. It may well be another 30 years, or more, until we see a show like this again.

Basking in the benevolent glow of these uplifting, life-enhancing portraits, it seems remarkable that Hals ever fell out of favour — yet for long periods he’s been belittled, a distant third in the pantheon of Dutch Masters, way behind Rembrandt and Vermeer. Acclaimed in his own time for dashing paintings that “live and breathe”, he was neglected in the 18th century, revived in the 19th century, and then sidelined in the 20th century (Kenneth Clark, in a rare lapse of taste, called him “revoltingly cheerful and odiously skilful”). Now, happily, in the 21st century, his time has come around again.

These 400-year-old portraits feel so relevant today because they celebrate the best things in life — love and marriage, friendship and fidelity. We’re beginning to realise, belatedly, that these cornerstones of contentment are more valuable than ever. In our brave new world of AI and social media, where selfies have replaced proper portraits, the flirty, boozy banter of Frans Hals’ Golden Age looks more appealing than ever.

Frans Hals is at the National Gallery in London until 21 January 2024, and then at the Rijksmuseum in Amsterdam from 16 February to 9 June 2024, and the Gemäldegalerie in Berlin from 12 July to 3 November 2024.