The red carpet provided a chance for leading actors and actresses to show off their style with a number championing creations from this side of the pond.
Co-host Amy Poehler, who perhaps had the spotlight on her the longest, chose to wear three custom-designed gowns by English fashion designer Stella McCartney.
Arriving in a figure-hugging black cady gown on the red carpet, she changed into a forest green lace dress for her hosting duties before stepping into a strapless black and white silk panelled gown.
Savile Row-based tailors Spencer Hart dressed some of the biggest stars of the night in bespoke suits, including Benedict Cumberbatch, Dan Stevens, Alfonso Cuaron, Tom Felton, Rufus Sewell and Jason Statham.
Helen Mirren wore a light shade of green in a bespoke jade tulle and chiffon gown with a draped waist and an orchid-flower design from Jenny Packham, a designer often favoured by Kate Middleton.
Model Heidi Klum arrived in a daring black and white intricate gown with a train by the British-born fashion brand Marchesa.
Meanwhile, in the style stakes, the reliably on-trend Emma Watson looked stunning, despite an unusual decision to team a long red open-backed gown with a pair of tight fitted black trousers.
The Downton Abbey actresses Laura Carmichael and Michelle Dockery dazzled, with Carmichael almost unrecognisable in a fitted white strapless dress and Dockery earning another red carpet win in a strapless silver down with a higher hem line at the front.
Emma Thompson, who took her daughter along as her date for the evening, looked elegant in a vintage gold and black dress but she took a more relaxed approach to presenting by taking to the stage barefoot. Holding her Christian Louboutin heels in one hand, the actress referred to her aching feet while jokingly discussing the shoes' signature red soles: "I just want you to know, this red? It's my blood."