The meaning behind the Duchess of Cambridge's new 'Prussian blue' coat

The Duchess of Cambridge left Poland this morning, flying to Germany for the second leg of her latest European tour.Throughout the trip so far Kate has been communicating subtle messages via her clothing, and this morning???s coatdress by Catherine Walker & Co. was no exception.

The brand is a thoroughly British institution (and one that was adored by Diana, Princess of Wales in her lifetime) but today???s meaning was all in the colour.

Berlin Blue, or Prussian Blue, is a pigment that was first developed in Berlin in the early 18th Century, and became the lead colour for the Prussian Army and for other German military uniforms up until the First World War when grey became the staple.

The hue is also known as Cornflower Blue - the cornflower becoming a national flower in Germany thanks to tales of Queen Louise of Prussia, who fled Berlin as Napoleon pursued, and hid her children in a field of the flowers.Given that backstory, it seemed appropriate that Kate was surrounded by her children dressed in the same hue as they landed at Berlin"s Tegel airport.

If you adjust your set slightly, you may also want to see it as a Royal Blue - a decidedly British hue coined by millers in Somerset, during a contest to make a dress for King George III???s wife, Queen Charlotte, in the late 1700s.The debate as to exactly who can claim the shade as their own rumbles on, but needless to say the Duchess has been diplomatic in ensuring that there is something in there for everyone.

Coordinating her colour palette with her daughter, Princess Charlotte,Kate cut a graphic, streamlined silhouette on the airport runway, something that Catherine Walker & Co. co-founder and head of design, Said Cyrus, has previously told The Telegraphis a key consideration when he designs.

???We don???t usually suggest a jacket, as our coatdresses present a single, elongated look which we think is more elegant,??? he says.???Our coatdresses are made by skilled tailors and in photographs their strong silhouettes work well at every angle.The most popular styles are our Melrose Coatdress worn with the Florence Dress or the Melrose Dress.???

The Duchess has previously worn Cyrus???s Melrose style coatdress on several occasions - perhaps most notably when she commissioned a hybrid version of it, mixed with the also-popular Rosa Coatdress, to wear to a church service celebrating the Queen???s 90th birthday last year.

As she lands in Germany there will be plenty more opportunities to make a statement by dressing in labels establishedin the host nation, or even by adopting colours from the German flag.Don"t laugh too hard at that last point - Kate did it in Canada right down to the maple leaves, and the people duly loved it.

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