'We changed the hairstyles and the clothes of the world, including America.

They were a very square and sorry lot when we went over,” quipped John Lennon once.

He wasn’t wrong, though. From top to toe, east to west, The Beatles’ effect on fashion in the 1960s was massive. But the effect that fashion in turn had on The Beatles, and the extent to which their love of dressing up influenced their own sartorial choices, has been less well documented. Step forward, then, critic and uber-Mod Paolo Hewitt, whose new book, Fab Gear: The Beatles And Fashion, sets out to do just that.

Billy Hatton, who knew The Beatles in the early days, tells of sailors returning from New York who introduced the latest fashions to the city – jeans, for instance – and how pervasive the Teddy Boy look became there in the late 1950s. He also tracks down people who knew the band in later years, such as John Pearse, co-owner of the famous King’s Road hippie shop, Granny Takes A Trip.

Hewitt is helped by the fact that few bands had as many different “looks” as The Beatles, even though we tend to think of only two: the suits of the Beatlemania period, and the circus dandy gear of the Sgt Pepper era. In fact there were many more: the Teddy Boy style during their first spell in Hamburg, the leather look of 1962, the collarless Fab Four suits, and the shag-haired look of the Revolver period.

There were the beads and kaftans of their 1968 Indian sojourn and the flared suits of the post-Pepper years, designed by Kilburn wide boy Tommy Nutter and cut by Savile Row veteran Edward Sexton, commemorated on the famous cover of 1969’s Abbey Road album.

Hewitt’s book is also full of other fascinating titbits. Did you know that Sexton would later mentor Stella McCartney as she began her fashion career? Or that as a boy George Harrison did the rounds of the Liverpool cobblers asking if they could make him a pair of corduroy boots? They just laughed

The Beatles’ relationship with fashion was restless, inventive and confrontational – witness their adoption of the moustache in the late 1960s (a time, says their former hairdresser Leslie Cavendish, when they were worn only by “spivs and old people”). But at heart, Hewitt thinks, they were just four young men who loved dressing up, whether it was climbing into cowboy gear for a photo shoot, donning a false beard and joining the press pack as McCartney once did, or arriving at the back door of an awards ceremony dressed as chefs. In an age of all-powerful stylists and dress-by-numbers pop wannabes, we would do well to remember that. n

Fab Gear: The Beatles And Fashion by Paolo Hewitt is out now (Prestel, £29.99)