Question: When was the first world war broke out?
Disambiguated questions and answers: question: When was the first world war broke out as measured by when Gavrilo Princip was assassinated?
When was the first world war broke out as measured by when Austria-Hungary first shelled Belgrade?
answer: 28 June 1914
28 July 1914
Natural Questions answer: 28 July 1914 (from the Wikipedia article "World War I")