World War I casualties
The total number of deaths includes from 9 to 11 million military personnel. The civilian death toll was about 8 million, including about 6 million due to war-related famine and disease. The Triple Entente (also known as the Allies) lost about 6 million military personnel while the Central Powers lost about 4 million. At least 2 million died from diseases and 6 million went missing, presumed dead. This article lists the casualties of the belligerent powers based on official published sources.
The March (1945)
The total number of US POWs in Germany was in the region of 93,000-94,000 and official sources claim that 1,121 died. The British Commonwealth total was close to 180,000 and while no accurate records exist, if a similar casualty rate is assumed, the number who died would be around 2,200. Therefore, according to a report by the US Department of Veterans' Affairs, almost 3,500 US and Commonwealth POWs died as a result of the marches. It is possible that some of these deaths occurred before the death marches, but the marches would have claimed the vast majority.