Civilian casualty ratio
Some 7 million combatants on both sides are estimated to have died during World War I, along with an estimated 10 million non-combatants, including 6.6 million civilians. The civilian casualty ratio in this estimate would be about 59%. Boris Urlanis notes a lack of data on civilian losses in the Ottoman Empire, but estimates 8.6 million military killed and dead and 6 million civilians killed and dead in the other warring countries. The civilian casualty ratio in this estimate would be about 42%. Most of the civilian fatalities were due to famine, typhus, or Spanish flu rather than combat action. The relatively low ratio of civilian casualties in this war is due to the fact that the front lines on the main battlefront, the Western Front, were static for most of the war, so that civilians were able to avoid the combat zones.
Portugal during World War I
Approximately 12,000 Portuguese troops died during the course of World War I, including Africans who served in its armed forces in the colonial front. Civilian deaths in Portugal exceeded 220,000: 82,000 caused by food shortages and 138,000 by the Spanish flu.
When Portugal complies with the British request to confiscate the German ships interned in Portuguese ports, Germany reacts by declaring war on Portugal, thus forcing the Portuguese officially into the war.The war causes Portugal 8,145 dead, 13,751 wounded and 12,318 prisoners or missing. At sea, 96 Portuguese ships are sunk (100,193 tons) and 5 Portuguese ships damaged (7,485 tons) by German submarines.