Silk Escape and Evasion Maps

Purpose and Operational Context

During the Second World War, the risk of being shot down behind enemy lines or captured in occupied territory was a constant reality for Allied aircrews and special operations personnel. To increase the chances of survival and successful return to friendly territory, military intelligence agencies developed specialized “Escape and Evasion” (E&E) maps [2].

Unlike standard paper maps, which were bulky, fragile, and produced a distinct rustling sound when unfolded—potentially alerting enemy patrols—E&E maps were printed on materials designed for clandestine use. These maps provided essential geographic data to help personnel navigate toward neutral borders or military bases while remaining undetected [1].

Development and Design

Material Composition

While commonly referred to as “silk maps,” these documents were printed on a variety of durable, lightweight fabrics and materials [3]. The primary choices included:

• Silk: Highly valued for its strength and the fact that it does not rustle during nighttime use [1].
• Rayon: A man-made fabric used as an alternative to silk [3].
• Tissue Paper: Used in some instances for extreme lightness [3].

Technical Characteristics

The design of these maps prioritized concealment and durability. Because the fabrics were flexible, the maps could be folded into extremely compact sizes, allowing them to be hidden in clothing, boot linings, or other personal effects [1, 3]. To ensure the maps remained legible in harsh field conditions, they were printed with waterproof dyes, preventing the colors from running if the material became wet [1].

Production and Distribution

The Role of MI9

In the United Kingdom, the production of E&E maps was the responsibility of Military Intelligence Section 9 (MI9), established in December 1939 [2]. MI9’s primary objectives included facilitating the escape of British prisoners of war (POWs) and aiding those evading capture in occupied territories [2].

MI9 produced a vast array of these maps—at least 234 individual maps have been identified in historical research—based on existing source maps [4]. Because the geographic information was similar to that of common travel maps and not considered highly secretive, MI9 managed the production independently rather than utilizing overworked military cartography branches [3].

Distribution and Use

All Allied aircrew were typically supplied with these maps in the event they were shot down [3]. Beyond official issuance, many maps were smuggled into POW camps through ingenious methods to assist prisoners in their escape attempts [3]. In some cases, prisoners adapted the materials for other uses; for example, one surviving example shows a lampshade constructed from MI9 maps [2].

OSS Equivalents

The Office of Strategic Services (OSS) in the United States employed similar technology. OSS silk maps often included additional utility, such as translated messages asking for assistance in returning to a military base, acknowledging the language barriers agents and soldiers faced in foreign territories [1].

Historical Significance and Legacy

The development of fabric maps represented a critical intersection of cartography and clandestine tradecraft. By prioritizing the physical properties of the medium—silence, durability, and compactness—MI9 and the OSS provided personnel with a tangible tool for survival in high-risk environments.

Today, these maps are preserved in various museum collections, including the CIA Museum and the Australian War Memorial, serving as artifacts of the logistical ingenuity required to support special operations and evasion efforts during the global conflict [1, 2].