“It is time that the spirit of fun was introduced into furniture and into fabrics. We have suffered too long from the dull and the stupidly serious.” So said Roger Fry in 1913. Roger Fry (1866-1934), artist, art critic, art exhibition organiser and champion of Cézanne and the Post Impressionists, had a huge influence on British thinking on art in the early 20th century.

In 1913, he founded the Omega Workshops in a residential property in Fitzroy Square, Bloomsbury, the heart of bohemian London.

Fry wanted them to be a “laboratory of radical design ideas”, that is a combined artists’ studio, shop and gallery space where avant-garde artists could work producing well-designed objects for the home that expressed the artist’s making, not, as Fry said, the “deadness of mechanical reproduction”.

It was a contrast to the department stores that were taking over London’s shopping areas at the time, selling mass-produced goods in new and exciting ways.

There was nothing quite like the Omega shopping experience.

It was highly personal, customers mixing with and discussing designs with the artists, and the goods on sale, from rugs and linens to ceramics, furniture and clothing, were inspired by contemporary art in Europe.

The Quaker Fry infused many of his ideals into the workshops, his pacifism for one, and enforced a ‘rule of anonymity’ on his artists.

These included Vanessa Bell, Duncan Grant, Wyndham Lewis, Frederick Etchells, Henri Gaudier-Brzeska and Winifred Gill, whose work bore only the Greek letter omega in a square, the same symbol as on the signboard outside.

The customers were generally wealthy and ranged from Virginia Woolf to George Bernard Shaw, H.G. Wells, W.B. Yeats and E.M. Forster, as well as bohemian high society figures like Ottoline Morrell and Maud Cunard.

Omega’s products were exciting, boldly coloured and patterned with dynamic abstract designs. And thoroughly covetable, though I’m less sure about Fry’s ceramics.

But you can see for yourself in the Courtauld Gallery’s current exhibition that dips into its collection of working drawings from the Omega Workshops bequeathed by Fry’s daughter in 1958 to take a look at this highly creative, if short-lived, moment in British design history.

From beginning to end, as you delve into this “largely unknown treasure” as the Courtauld puts it, from the first flash of saturated colours and crisscrossing diagonals, from textiles, rugs, screens and designs, you get a taste of what it must have been like to enter that singular place.

The exhibition divides into two parts plus a related display: textiles and textile designs; a few ceramics (including — and you’ll either love or hate them — a row of terracotta cats by French sculptor Gaudier-Brzeska, each glazed a different colour), furniture, embroideries, and Fry’s venture into book publishing; finally, in a neighbouring room, rarely seen works on paper by “the unsung heroine of the Omega Workshops”, the designer dress maker Winfred Gill (including a fun little group of articulated toy designs, the best being the cobalt blue butterfly/fairy dancer and Admiral Jellicoe about to do a jig).

Let’s look at some highlights.

First, Vanessa Bell’s painted screen, Bathers in a Landscape, based on sketches she and Duncan Grant made on a camping trip to Norfolk. It’s also called Tents and Figures. Not that you’d know it, although the bathers are pretty clear, sea green in colour, the tent poles are reduced to slanting grey and yellow lines lined in black.

It’s a spirited design with a wonderful sense of movement, aided by the screen’s folds. And it’s important art historically as a transitional work between fine and decorative art. Alongside are three of its working design drawings and an eye-catching rug made for Lady Ian Hamilton’s Mayfair flat.

It is notable how the finished rugs retain the informal quality of the original drawings. This was intentional, an important part of the Omega’s modernist aesthetic.

The one in the centre of the gallery, for instance, has mildly jagged, broken lines dividing its spaces, providing a sort of loose visual scaffolding around the colours. Fry would deliberately break up lines, seeking a geometry that could be repeated as a design but at the same time would give a fresh breath of air.

The Peacock Stole takes pride of place. This long chiffon silk stole painted in primary colours with a bold motif of pairs of peacocks confronting one another has not been on view for over 50 years; it comes to the exhibition straight from conservation and is reunited with two preparatory drawings.

It really is fabulous; though perhaps because it is more amazing to look at than practical, it remained unsold. Immediately opposite is a row of designs with textiles beneath, some attributed to Bell, others to Grant. With their strong compositions and vibrant palette, they reminded me of the Russian Constructivist Liubov Popova’s 1918 Painterly Architectronics series recently seen at Tate Modern.

I asked the curator about this. She said while she was working at the same time, there was no known direct influence. Omega’s designs were discussed in a Russian avant-garde journal and there was “in terms of design, a seeping through of British ideas to Russia”.

Other influences are: Picasso, Cubism, African, Japanese, Arts and Crafts (if not directly), and there are echoes of Kandinsky in the rug design by Bell named Maud after its high-society patron, Lady Cunard.

This explains why the exhibition is called Beyond Bloomsbury. The Courtauld aims, it says, to lift the Omega Workshops out of the context of the Bloomsbury Group of artists and intellectuals in which it is so often seen, instead to consider it “an ambitious experiment in design with a far-reaching influence, particularly in the field of artist-designed textiles in Britain”.

lBeyond Bloomsbury: Designs of the Omega Workshops 1913-19 is at the Courtauld Gallery, Somerset House, London until September 20.