 While civilian communities had organized ways to deal with prehospitalisation care and transportation of the sick and dying as far back as the bubonic plague in London between 1598 and 1665, such arrangements were typically "ad hoc" and temporary.In time, however, these arrangements began to formalize and become permanent.During the American Civil War, Jonathan Letterman devised a system of mobile field hospitals employing the first uses of the principles of triage.