Date of Graduation


Document Type


Degree Type



Eberly College of Arts and Sciences


Political Science

Committee Chair

Donley T Studiar


The selection of a military recruitment method has historically been based on material capabilities and military objectives. Recruitment strategies range from coercively conscripting soldiers to encouraging volunteer enlistments. Historically, states around the globe have used large conscripted armies to wage war when they become fully mobilized for protracted military engagements against another state. However, the occurrence of war is by its very nature a rare occurrence in the international system. This begs the question of what types of military recruitment states are using as a function of choice rather than necessity.;Existing literature on the selection of force structure is far more complex than existing historical models would imply. A range of factors including material capabilities, geopolitical conditions, foreign policy objectives, and institutional characteristics have all been proposed as potential explanations for the adoption of military manpower systems. These factors reflect the wide degree of variation among states in their choice of recruitment strategy. Existing case literature implies that states with similar geographic and socio-economic conditions may cluster around a given recruitment method. However, much of the realist scholarship in international relations implies a strong emphasis on power or security maximization, thus implying a more uniform policy calculus. However, there has been little theoretical or empirical research in political science or geography to date that effectively addresses this crucial policy area.;This study explores the relationship between physical geography, environmental factors, and force structure in order to investigate a small portion of the classical geopolitics literature. In order to investigate the problem of recruitment strategy, this study must develop a metric for comparison. Geographic Information Science (GIS) is used to develop an Index of Strategic Vulnerability for all states in the international system. This measure is composed of geographic and environmental variables including elevation, area, precipitation, and temperature. Data generated in the GIS are used to conduct duration models to examine the effects of geographic and environmental variables on the length of militarized interstate disputes. The results of this analysis indicate that increasingly difficult geographic and environmental conditions produce significantly longer conflicts. These finding provide empirical support for the existing case literature that claims geography and environmental factors matter in the conduct of war.;Next, the geographic and environmental data are used with political and institutional control variables to empirically evaluate the relationship between force structure and the operational conditions. Statistical analysis is used to empirically test the impacts of geographic and environmental variables have on force structure. Results indicate that geographic factor of size increases the probability that a state will use conscription. The only environmental factor to achieve significance was a state's annual level of precipitation which favored the use of volunteer forces. These findings indicate that there is a tremendous amount of variation in terms of geographic and environmental conditions that states face. This also means that the adoption of military manpower policies in the international system is a reflection of these operational conditions.