Keystone USA, with its origins in the 1870s, is one of the largest and most important historic photo collections in the world. This extensive collection, arguably the best visual history of the 20th century, documents international political and world news events, diplomacy, royalty and ceremonial occasions. It also covers fashion, sport, celebrity and the entertainment industry, and includes social history and local news events.

As you might expect, there are some real crackers in this collection, such as the above image of Laurence Olivier in costume as Richard III sitting for Salvador Dali in Shepperton Studios in 1955.

To save you the Herculean task of looking through the 155,000 Keystone USA images now on our website, we've edited it down to a mere 500, which you can browse here at your leisure.

As always, we are on hand if you can't find what you're looking for, or would like a quote. Please contact pictures@maryevans.com or call us on 020 8318 0034.