The triceps that launched a thousand think pieces, 2010

With Michelle Obama’s signature look – a sleeveless dress that made a feature of her worked-out arms – she reset the dial for alpha females. For a speech to launch her Let’s Move campaign, encouraging young people to be fit and healthy, she wore a chic sheath dress and a string of pearls (so far, so Camelot) but her bare arms grabbed the fashion headlines. Beneath the sniffy controversy over whether the look lacked gravitas was an establishment unease with this new kind of first lady, who radiated energy and strength rather than decorative decorum. Where Michelle led, a decade of glamour players followed. (See also: Gwyneth Paltrow, CEO with killer abs.)

The unmissable bottom, 2011

Facebook Twitter Pinterest Pippa Middleton at the wedding of her sister Kate in 2011. Photograph: Chris Jackson/Getty Images

The scene stealer at the royal wedding in April 2011 was bridesmaid Pippa Middleton’s back view as she carried her sister’s train into Westminster Abbey. In a startling about-turn from the previous decade, in which the hoped-for answer to the perennial question “Does my bum look big in this?” was negative, the 2010s was all about the triumph of the curvy bottom. In 2014, Kim Kardashian broke the internet balancing a champagne coupe on her backside for the cover of Paper magazine, while Beyoncé wore an almost-sheer Givenchy gown to the Met Gala the following year. The hipster cut, which had been minimising bottoms, swiftly made way for high-rise, tightly waisted denim jeans and cut-offs, as the bottom became fashion’s biggest hit.

Patient zero of the golden age of television, 2012

Facebook Twitter Pinterest Jodie Comer in that Molly Goddard dress in Killing Eve. Photograph: PA

This was the decade in which watching television shifted from being a vaguely downmarket pastime to a status activity. Boxset one-upmanship led the conversation at the kind of dinner parties where once no one would have admitted to watching television at all. And fashion was a major player in the telenaissance, with wardrobe adding style and depth to the Spielberg Americana of Stranger Things, and bringing painterly colours and sensual textures to The Marvelous Mrs Maisel. But Christina Hendricks as Joan in Mad Men was the trailblazer when it came to clothes as character study and social commentary: without Joan’s red dress, there would be no Killing Eve pink tulle, no Fleabag jumpsuit.

Dawn of the mid-length skirt, 2013

If I had to condense the evolution of this decade into three words it would be this: Skirts Got Longer. The default skirt length has shifted from knee to just-above to mid-calf. The reasons behind these extra inches are many, and include the increased importance of the Middle Eastern and Asian markets; more demand from older women; and the traditional correlation of a wobbly economy with plunging hemlines. By 2013 the mid-length skirt had stormed the catwalk. At New York fashion week in September, Vogue reported on the ubiquity of below-the-knee, predicting that “wearing that graceful new length is certain to be the sensation of next summer”. On the Burberry catwalk in London the following week, Cara Delevingne in a sheer, elongated pencil skirt made it official.

Facebook Twitter Pinterest Cara Delevingne walks the runway at the Burberry Prorsum show during London fashion week in September 2013. Photograph: Antonio de Moraes Barros Filho/WireImage

A lightning rod of moral panic became the luxury must-have, 2014

The hoodie is the joker of this decade’s fashion pack. It has been a marker of street crime, a visual bogeyman captured on grainy surveillance camera footage, a low-watermark of declining sartorial standards, a badge of disaffected youth. But it has also been the breakout fashion hit, with a spendy price tag to match. In 2014, Givenchy put designer hoodies on the Paris catwalk, styled with black mesh face masks; Kanye West wore a grey marl hoodie under a camel coat in the front row. Rihanna supersized the look with a DKNY hoodie dress, and new cult label Vetements launched £800 hoodies, which promptly sold out. Once you paid for craftsmanship; now you paid for cool.

‘Call me Caitlyn’, 2015

Facebook Twitter Pinterest Caitlyn Jenner’s Vanity Fair cover. Photograph: Getty Images

Let us begin by saying that the experiences and rights of transgender people are in no way a trend to be decreed in or out of vogue. Having established that, allow me to acknowledge that this was the era when trans became a talking point in mainstream culture, and fashion played a role. Caitlyn Jenner’s iconic Vanity Fair cover marshalled the traditional arsenal of the glossy magazine playbook in the cause of winning the hearts and minds of the US. Stylist Jessica Diehl put images of Lauren Bacall and Jackie Kennedy on her moodboard as she planned the bridal white satin, the hourglass silhouette and tumbling curls. Perhaps the most iconic cover since Demi Moore’s baby bump.

Fashion discovers feminism, 2016

Facebook Twitter Pinterest A model wearing a white T-shirt with the print ‘We should all be feminists’. Photograph: Christian Vierig/Getty Images

The slogan T-shirt was widely believed to have peaked in 1984, the year Wham set off those iconic suntans with crisp white Choose Life Ts, Frankie Goes to Hollywood told us to Relax, and Katharine Hamnett wore her “58% Don’t Want Pershing” to Downing Street. But when Maria Grazia Chiuri became the first female creative director of Christian Dior, a house as synonymous with femininity as Chanel is with chic, the talking point of her first collection was a T-shirt printed with the words “WE SHOULD ALL BE FEMINISTS”, the title of an essay by Chimamanda Ngozi Adichie. If Dior stands for femininity, Chiuri said, then that should represent the whole of the female experience, not just an aesthetic. Feminism via a £500 designer T-shirt drew more than a few critics, but it also rebooted the slogan as a modern fashion classic.

Politics goes haywire, with power dressing to match, 2017

Facebook Twitter Pinterest Melania Trump wears her heart on her back. Photograph: Getty Images

In Sicily, on Melania Trump’s first foreign trip as first lady, she wore an applique floral Dolce & Gabbana coat with a $51,500 price tag – just under the median American annual household income. It was a choice made all the more politically charged by the fact she had been publicly snubbed by prominent US designers, including Tom Ford and Marc Jacobs. The coat flaunted her pride in her status as one of the super rich, and was a defiant riposte to any suggestion she might tread carefully around the divisive issue of inequality. The following year, the Dolce coat was relegated to a footnote when Melania wore a Zara coat bearing the slogan, “I Really Don’t Care, Do U?” on a visit to a centre for migrant children in Texas.

Body obsession goes equal ops as Love Island takes over, 2018

Love Island was the surprise watercooler phenomenon of summer 2018, leaping from adolescent guilty pleasure to national obsession. And while nubile young women in televised swimsuit parades were nothing new, the sight of obsessively buffed men engaging in open competition was a novelty. This gender-blind peacock glamour, which was at the very same time making Gucci the buzziest name in high-fashion, was here given a soft-porn makeover. Men who had never given much consideration to their “holiday look” beyond replacing a pair of trunks when the drawstring finally snapped were introduced to the phenomena of “leg day” at the gym, hotwaxing and fake tanning.

Facebook Twitter Pinterest Love Island 2018. Composite: The Guide

We’re still wearing polo necks, 2019

After a rollercoaster decade, what are we wearing? Why, the very same garment we began wearing almost 10 years ago – the polo neck. It is amazing to think, now, that in the noughties, the polo neck was an outre fashion choice favoured only by Steve Jobs and the Milk Tray man. In the 2010s, everyone – starting with Phoebe Philo, but running through Harry Styles and Victoria Beckham to Héctor Bellerín and Shiv in Succession – wore a polo neck. The Maxmara catwalk show for autumn 2019 opened with three polo-neck looks – one lemon yellow, one electric blue, one aquamarine. Designer Ian Griffiths said the show was about “the politics of glamour”. Which about sums this decade up.

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