Norman Hartnell used to refer to his competitor Hardy Amies as ‘Hardly Amiable’, according to Michael Pick, guest curator on Hartnell to Amies Couture By Royal Appointment, the exhibition that opens tomorrow at the Fashion and Textile Museum.

Pick also reports that Sir Hardy Amies once said ‘the great difference between us is that I’m a bitchy old queen and Hartnell’s a soppy old queen’. All of which makes you wonder what these former titans of fashion might have thought about being placed side by side in an exhibition celebrating British couture.

The exhibition explores how the Queen’s patronage of these British designers helped to establish London as an international fashion centre after the Second World War. Hartnell, who opened his couture house in 1923, famously designed the Queen’s wedding dress in 1947 and Coronation dress of 1953.

Amies, meanwhile, enjoyed the patronage of HRH Queen Elizabeth for five decades, from when she was a Princess in respectable tweed suits to some of her more recent memorable on-tour and occasion outfits in pristine pink, lemon and mauve. ‘Hardy had a view of fashion,’ points out Freddy Fox, the milliner responsible for the Queen’s most photo-worthy hats which are given apt prominence in the exhibition,‘It was all about taking things off with Hardy; less is more, he looked for proportion.’

While Hartnell’s style was typically more lavish – as captured beautifully by Norman Parkinson’s photographs that provide an important backdrop to the exhibition. A black velvet coat, made in the 1930s by Hartnell, is bejewelled to within an inch of its life – and, bizarrely, all the more modern for it, in a

What the exhibition shows is that whoever they were dressing, be it aristocracy, ‘bancocracy’ (what Fox calls the mega-wealthy) or movie stars (from Marlene Dietrich to Elizabeth Taylor), these couturiers were able to move with the times – from dropping to the longer lengths of the 1930s to ratcheting up hemlines and stripping-back looks for the 1960s.

Although Hartnell hated the mini skirt; he thought that women’s knees and elbows looked like ‘underdone rock cakes’. It's a well thought out show with some exceptional pieces to see - a sweeping green 1970s off-the-shoulder gown by Hartnell or a crisp, patterned cinch-waist 1980s number by Amies, along with all the grand aristo wedding gowns which makes you think of Kate Middleton and her patronage of

What a show that would be - to bring British couture bang up to date with the new generation of designers who are helping to shape the iconic looks of royal and political celebrity. Perhaps that could be the Fashion and Textile Museum’s next venture: Couture By Royal Appointment Part Two?

The Fashion and Textile Museum, 83 Bermondsey Street, London SE1 3XF, exhibition dates 16th November – 23rdFebruary 2013. Exhibition opening times: Tuesday-Saturday, 11am-6pm; last admission 5.15pm.Ticket prices: £7 adults, £5 students and concessions, free entry under 12s

See all of Kate Middleton's repeat looks here