Royal Armouries is conducting groundbreaking research to establish if a bullet-proof silk vest could have saved Archduke Franz Ferdinand’s life – and changed the course of history.

Experts at the National Firearms Centre in Leeds have replicated the conditions of the Archduke’s assassination in 1914 as accurately as possible, forming a key part of the museum’s First World War centenary programme.

Further experiments to test the capabilities of late 19th century body armour against 20th century firepower will go ahead in early September, but initial results have borne out a widely-held theory that silk does have bullet-stopping capabilities.

At the time, reporters speculated that the Archduke owned, but failed to wear, a piece of silk body armour on June 28 1914, when he was assassinated, along with his wife, Sophie, by a lone gunman in Sarajevo. The killings triggered a rapid chain of events, widely acknowledged to have sparked the outbreak of the First World War – a conflict that left a lasting legacy, which still echoes today.

Royal Armouries’ tests involve recreating replica silk vests. Made to the original patent’s specifications, these replicas have been fired at with the same type of pistol and ammunition and from the same distance as the original event.

Devised by priest-turned-inventor, Casimir Zeglen, this armour comprised organic layers, most notably silk, which had the ability to resist bullets. By the early 1900s, these vests were sold globally, and were bought by European royalty and heads of state.

Royal Armouries’ First World War researcher Lisa Traynor said, “In a previous role, I stumbled across a Browning Model 1910 self-loading pistol, the same type used to assassinate the Archduke. Upon examining its serial number, I realised it was only 516 away from the actual pistol used in the assassination and would probably have been manufactured around the same time.
“This made me think about the ‘what if scenario’ surrounding the death of the Archduke. If he hadn’t been killed, would the war have been delayed?

“After months of independent research in international archives and with the assistance of international academics on the subject, I discovered that it was entirely possible that the Archduke may have owned a piece of body armour. Our First World War team thought it would be interesting to test the theory of silk body armour against the Browning Model 1910, to understand the ballistic capabilities of 19th century body armour against 20th century firepower.”

“I don’t want to pre-empt the next round of tests, however I can report that silk does have bullet-stopping capabilities! So this research could result in very exciting results.”

This ground-breaking research will form part of a new permanent exhibition at the Royal Armouries in Leeds, due to open in September – Bullets, Blades and Battle Bowlers.

Funded by the DCMS/Wolfson Galleries Improvement Fund, the exhibition will share the stories of inventors, tacticians and soldiers of different nationalities. Through their individual stories, it will explore how technological advances helped catapult the world into an era of modern warfare. The displays in the museum’s War Gallery will also explain how these bullet proof vests were constructed; show footage of the experiments against the Browning pistol; and feature silk vest samples.

Franz Ferdinand and the Mystery of The Silk Vest – Lisa is delivering a talk at the Royal Armouries Museum in Leeds on September 24, which will shed fresh light on the issue, and reveal the results from the upcoming tests. For tickets, priced £5, and more information, visit

Lisa is also presenting an international paper focused on the research at the International Committee for the History of Technology’s Conference in Romania, which runs from July 29 to August 2.

For more information regarding Royal Armouries’ First World War programme, visit

Notes to editors

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