Throughout human history, advancements in medicine have evolved out of periods of war. The carnage of battlefield injuries provided wartime surgeons an unprecedented opportunity to study anatomy, develop novel techniques, and improve systems of care. As a specialty that was established and evolved during the first half of the 20th century, neurological surgery was heavily influenced by the experiences of its founders during the World Wars I and II. Utilizing the published Neurosurgery Tree, the authors conducted an academic genealogical analysis to systematically define the influence of wartime service on neurosurgery's earliest generations. Through review of the literature and military records, the authors determined that at least 60% of American neurosurgical founders and early leaders served during World Wars I and/or II. Inspired by the call to serve their nation as forces for good, these individuals were heralded as expert clinicians, innovative systems thinkers, and prolific researchers. Importantly, the service of these early leaders helped highlight the viability of neurosurgery as a distinct specialty and provided a framework for early neurosurgical education and expansion. The equipment, techniques, and guidelines that were developed during these wars, such as management of craniocerebral trauma, peripheral nerve repair, and hemostasis, set the foundation for modern neurosurgical practice.