Renoir's lasting impression

La Loge, Renoir's picture of an elegant couple in their box at the theatre, was his major contribution to the first Impressionist exhibition, held in Paris in 1874. The painting attracted a lot of attention and helped establish Renoir's reputation as a key figure in a radical new art movement that set out to capture fleeting impressions of contemporary life.

The painting remains to this day one of the most well-known Impressionist images and is a highlight of the Courtauld Gallery's permanent collection. Now, as part of their 75th anniversary celebrations, it is the centrepiece of an exhibition that focuses entirely on the small confined space of the theatre box to explore a range of issues from class and social mobility, to gender, fashion, and aspiration.

Concentrating on the early years of Impressionism in 1870s' Paris, the exhibition unites La Loge with other paintings on the theme by Renoir and his Impressionist contemporaries such as Mary Cassatt and Edgar Degas. It also includes Dans La Loge, Renoir's smaller freer version of La Loge made the following year possibly in response to critical success, and sold this February at Sotheby's to a private buyer for £7.4m, three times its pre-sale estimate.

After the paintings, there is an array of material to enjoy from contemporary fashion magazines and satirical journals that helps put it into context. Wonderfully down to earth, the caricatures bring it all to life - and are great fun.

Let's look at some examples, starting with a few paintings showing loge' scenes before Renoir took up the theme, an oil by Honoré Daumier painted around 1854-7 and three 1860 watercolours by Constantin Guys.

Then, across the room, Renoir's undeniably impressive La Loge (The Theatre Box), epitomising the Impressionists' interest in the spectacle of modern life. For what could express this better than the theatre box, the place where fashionable men and women went to see and be seen.

Theatre was a booming industry in the second half of 19th-century Paris. It dominated its cultural life, was quintessentially modern and ephemeral - the perfect stage for indulging those perennial and heady pastimes, showing off one's finery, and watching others do the same.

It is the enigmatic and complex play of gazes depicted in La Loge that gives it its power. We have no idea who or what the pair are looking at. It's certainly not the performance. She gazes dreamily out, resting her opera glasses in her lap, better perhaps to show off her beauty. He meanwhile, sitting behind his wife or mistress, we don't know, leans back better to scan the auditorium.

These paintings draw us into thinking about the characters. Who, for example, is the girl in Renoir's Au théâtre (At the Theatre)? The ingénue's excitement is palpable as she eagerly leans forward in her seat to gain a better view of the performance. Using energetic fluid brushwork Renoir makes her bright young profile the centre of attention, setting her off against a blurrily animated crowd below and a just visible older companion behind her. It's a very engaging picture.

Similarly Mary Cassatt's first major painting of a theatre box, though for quite different reasons. In her At the Français or In the Loge, painted in 1878, Cassatt disrupts stereotypes by showing a woman who actively does the looking - she is the only Impressionist artist to do this. Her painting shows a soberly dressed woman, possibly in mourning, sitting alone in her box staring assertively through her glasses across the auditorium. We don't see what interests the woman so much, but we do see a man on the opposite side of the theatre who shows a keen interest in her.

American artist Cassatt's second theatre box scene, painted a year later, gives an altogether different view of women. Woman with a Pearl Necklace in a Loge portrays a glittering beauty in a low-cut gown in the full glare of the lights of the gilded auditorium (they kept the lights on during performances, I am told).

An ever expanding list of daily and weekly satirical journals, popular and fashion magazines charted the fast changing nature of French society in the late-19th century. Fashion illustrators and caricaturists seized upon the loge' as the perfect vehicle for their themes: what fashions to aspire to as in the hand-coloured engravings from La Mode Illustrée displayed, and social satire.

The caricaturists poked fun at the pretensions of high society and middle-class social aspirations, for example, the snobbery, vulgarity' of modern fashions, and the loge' as an ideal setting for seduction. So, in coloured plates from the Petit Journal Pour Rire we see Papa being chastised for speaking too loudly as though he is still in the cheap seats, Les Anglais a Paris in their awfulness, and two gentlemen' snidely discussing the virtues of the woman in their box. "What do you think of my little woman?" one asks. The other, looking at her heavily made-up face, replies, "Well well, I don't know, I'm not a connoisseur of painting."

You don't have to be a connoisseur of painting to enjoy this exhibition. Highly focussed, it is necessarily small and will make a gently enjoyable visit to the Courtauld in its anniversary year. There is also a complementary display of 19th century French drawings in a nearby room.

Renoir at the Theatre: Looking at La Loge' is open until May 25 at the Courtauld Gallery, Somerset House, Strand. Website: www.courtauld.ac.uk