Often unheralded during campaigns in every theater of war were the medical personnel manning the aid stations and field hospitals in combat zones, as well as the unarmed Army medics and Navy corpsmen attached to front-line units who braved the mayhem of battle to care for the wounded. Many of these medics and corpsmen were conscientious objectors who sought to contribute to the war effort without taking the lives of others. Others were pulled from the ranks and selected for these roles as a result of acute shortages of medical personnel and the likelihood of high casualties. An example of their extraordinary service and sacrifice came during the invasion of Iwo Jima in February 1945, when twenty-three doctors and 827 corpsmen were killed or wounded in just five weeks of fighting.