Mulberry’s in a New York state of mind, and we don’t mean the Jay-Z kind. The iconic British brand is celebrating its 40th birthday this month, and fresh from opening its first flagship store in the city, it kicked-off its world-wide anniversary tour with a debut party in New York last night.

Featuring a live set from Kasabian, Mulberry set up a Seventies-style mirrored dancefloor at Skylight West where guests – including Alexa Chung, who wore the Polly Push Lock trench and Mini Alexa from the label’s pre-SS12 collection, Anna Dello Russo, Leigh Lezark and Maggie Gyllenhaal, dressed in this season’s Happy Hedgerow print Tille wrap dress – mingled among animal-shaped balloons, inflatable hats, cheese and tomato toasties and fairy cakes.

Prizes for guessing the theme of the evening: a children’s birthday party. But there was stuff for the adults, too – Margaritas, mainly – and goodie bags filled with stickers and birthday badges.

The party was held on the rooftop of Skylight West, a stone’s throw away from Mulberry’s new flagship store on Spring Street – an old industrial building that’s been restored according to Mulberry’s signature architecture (circular follies made from over 8,000 hardback books to reference the site’s history as a printers, or stackable crates that form tables and benches).

Click through our gallery below to see pictures from last night’s party and a sneak peek of the new store…

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