Answer:
Social life also changed: women had to run businesses while the men were at war and labor laws started to be enforced due to mass production and mechanization. People all wanted better living standards. After WW1, the need for an international body of nations that promotes security and peace worldwide became evident.
World War I was a global military conflict from 1914 through 1918. It killed 9 million soldiers, wounded 21 million, and left 7 million disabled. Another 10 million civilians died. Germany and France each lost 80% of their male population aged between 15 and 49.