![Sienna Miller](https://hollywoodlife.com/wp-content/uploads/2021/12/Sienna-Miller-social-image.jpg?quality=100)
Sienna Miller won the heart of Hollywood from the moment she crossed the pond. Click through to check out the best snaps of the British actress through the years!
Sienna Miller won the hearts of Hollywood from the second she stepped onto the scene. The British actress – whose birthday is December 28 – has starred in films Alfie, Layer Cake, Casanova, Factory Girl, The Edge of Love, Hippie Hippie Shake, The Girl, Foxcatcher, and American Sniper, just to name a few. Her first-ever film was South Kensington, with Rupert Everett and Elle Macpherson.
Aside from being an actress, Sienna is also a model and fashion designer. The gorgeous blonde is known for her chic & impeccable style, often seen front row at fashion week or strutting down the red carpet at A-list premieres.
Sienna Miller has kept people smiling through her decades in show business. Scroll through the gallery to take a look at some of her best fashion moments in honor of her 42nd birthday on December 28!
Sienna Miller in 2023
![Sienna Miller in 2023](https://hollywoodlife.com/wp-content/uploads/2021/12/Sienna-Miller-2023.jpg?w=680)
Sienna Miller posing
![Sienna Miller posing](http://hollywoodlife.com/wp-content/uploads/2017/04/sienna-miller-2-1.jpg?w=680)
Sienna Miller at the ‘Wander Darkly’ Premiere
![Sienna Miller at the ‘Wander Darkly’ Premiere](http://hollywoodlife.com/wp-content/uploads/2017/04/sienna-miller-3-1.jpg?w=680)
Sienna Miller at the 2020 Sundance Film Festival
![Sienna Miller at the 2020 Sundance Film Festival](http://hollywoodlife.com/wp-content/uploads/2017/04/sienna-miller-4-1.jpg?w=680)
Sienna Miller at the 2020 Golden Globe Awards
![Sienna Miller at the 2020 Golden Globe Awards](http://hollywoodlife.com/wp-content/uploads/2017/04/sienna-miller-5-1.jpg?w=680)
Sienna Miller at a Screening of ‘American Woman’
![Sienna Miller at a Screening of ‘American Woman’](http://hollywoodlife.com/wp-content/uploads/2017/04/sienna-miller-6-1.jpg?w=680)
Sienna Miller at a Screening of ’21 Bridges’
![Sienna Miller at a Screening of ’21 Bridges’](http://hollywoodlife.com/wp-content/uploads/2017/04/sienna-miller-7-1.jpg?w=680)
Sienna Miller at the 23rd Annual Hollywood Film Awards
![Sienna Miller at the 23rd Annual Hollywood Film Awards](http://hollywoodlife.com/wp-content/uploads/2017/04/sienna-miller-1-1.jpg?w=680)
Sienna Miller Stuns at the 2010 Met Gala
![Sienna Miller Stuns at the 2010 Met Gala](https://hollywoodlife.com/wp-content/uploads/2017/04/sienna-miller-ss-01.jpg?w=680)
Sienna Miller Sizzles at Montblanc Charity Gala in 2009
![Sienna Miller Sizzles at Montblanc Charity Gala in 2009](https://hollywoodlife.com/wp-content/uploads/2017/04/sienna-miller-ss-05.jpg?w=680)
Sienna Miller at the British Academy Film Awards in 2007
![Sienna Miller at the British Academy Film Awards in 2007](https://hollywoodlife.com/wp-content/uploads/2017/04/sienna-miller-ss-04.jpg?w=680)
Sienna Miller Glows at the 2007 Golden Globes
![Sienna Miller Glows at the 2007 Golden Globes](https://hollywoodlife.com/wp-content/uploads/2017/04/sienna-miller-ss-03.jpg?w=680)
Sienna Miller Wows at the 2005 Venice Film Festival
![Sienna Miller Wows at the 2005 Venice Film Festival](https://hollywoodlife.com/wp-content/uploads/2017/04/sienna-miller-ss-02.jpg?w=680)