The Archaeology of World War II Karst Defences in the Pacific

Author: Julie Mushynsky

Mushynsky, Julie, 2017 The Archaeology of World War II Karst Defences in the Pacific, Flinders University, School of Humanities and Creative Arts

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During World War II (WWII) the Japanese military, themselves or by using civilian labour, excavated tunnels into the limestone of many Pacific islands and modified natural caves to use as command posts, hospitals and for combat, storage and shelter. Civilians also used caves to shelter themselves during WWII. In this thesis, caves and tunnels are considered a specific type of site constructed within a karst topography and are referred to as “karst defences.”

This study investigates karst defences in Saipan, Commonwealth of the Northern Mariana Islands. The thesis seeks to explore the defensive strategies people employed at karst defences and what influenced these tactics during the Battle for Saipan from June 15 to July 9, 1944. The research also examines how these strategies changed as the Battle for Saipan progressed and how they relate to the overall Japanese WWII defensive strategy in the Pacific.

Analysis incorporates archival research and archaeological fieldwork. Fieldwork included the detailed recording of over 50 sites across Saipan and their material remains. Data from Saipan was also compared to previous studies, particularly on Peleliu in Palau and Chuuk Lagoon (formerly Truk Lagoon) in the Caroline Islands. Collaborative methods were used during fieldwork which included collecting oral histories from civilians in Saipan who hid within caves during the battle, working with local co-researchers and employing volunteers. Through collaboration, this thesis also examined the significance of karst defences to people in the present.

Through an examination of material remains and site construction, comparative analysis and reconstructing the battlefield, this study argues that people’s behaviour during conflict is not motivated by sheer survival. This study revealed a range of defensive behaviours and strategies used by the Japanese military, the United States military and civilians. Strategies were influenced by military culture and changing war conditions and attitudes. The study also contributed new knowledge to and clarified popular historical understandings of overall Japanese and civilian defence strategy during the Pacific War. This is the first systematic, island-wide study of karst defences in Saipan and the first study in the Pacific to use karst defences to archaeologically analyse and interpret defensive strategies through space and time.

Keywords: World War II, karst defences, Saipan, Mariana Islands, Imperial Japanese military, Battle of Saipan

Subject: Humanities thesis, Creative Arts thesis

Thesis type: Doctor of Philosophy
Completed: 2017
School: School of Humanities and Creative Arts
Supervisor: Amy Roberts, Heather Burke