When this famous hat was displayed at an exhibition in 2003, Suzy Menkes said in The New York Times: "There is a particular combination of madness and dignity to the dashing tricorn that Aage Thaarup created".

[3] He had no hatmakers in his family, but would later say that his grandmother had made shoes for Queen Alexandra[4] Moving to London – on a one-way ticket using borrowed money – he sold hats for a time as a commercial traveller, but found he could not make enough to live on.

[2] Travelling on to other Indian cities, he continued making hats, getting help with construction and materials (many of which were improvised) from the men who sewed for a living in India's bazaars.

Nonetheless, he made his mark; a milliner in Lahore still (in 1961) had a sign painted above his shop bearing the legend: 'Noor Mohammed, late of Aage Thaarup (London & Paris) Model Hats'.

[3][5] This flair would mean he later moved his business to Grosvenor Street and began exporting his hats to high-end stores such as Lord & Taylor in New York.

It was said he planned to send shipments of the hats all over the world and a reporter from The Sydney Morning Herald gushed: "It has taken a Dane to turn 'London Pride'...into a symbol.

[2][10] For George VI's 1947 tour of South Africa, Norman Hartnell and Thaarup prepared the queen consort's garments by numbering every outfit and matching hat to ensure there was no confusion.

Thaarup also had to consider the vagaries of the climate in his designs – hat pins that resisted rust and fabrics that wouldn't be irresistible to insects.

He also included hats with ostrich feathers – a major South African export and highly prized by the garment and millinery industries.

[10] As milliner to Elizabeth II – and referred to as such by many media sources during the 1950s although his official Royal Warrant was not formally granted until 1961 – Thaarup was responsible for many hats captured in film and photographs.

"[2] At the Trooping of the Colour, the replacement of the monarch's traditional bearskin with a tricorn cap with osprey plume was considered contemporary when Princess Elizabeth first wore it in 1951 (standing in for her father who was unwell).

But it was also a practical modification, being more lightweight, and a contemporaneous account by the BBC said Thaarup had based it on an 18th-century regimental design, with the addition of the feather to soften what was otherwise a man's cap.

[2] These included ranges for Finningans in Bond Street and Marshall & Snelgrove[13][14] Thaarup was also highly active in promoting his name throughout his career – not only appearing in numerous British Pathé films, but also visiting high-street stores that stocked his non-bespoke hats twice a year to personally sell to the public both his own designs and those of his competitor milliners.

The reporter noted that the young girl wore the typical Chelsea outfit of white stockings, straight hair and plain dress and both she and the audience were delighted by the transforming effect of a design created by this: "dearly loved figure in the London fashion world".