1917
1921
1924
1925
When was the construction of Great Wall of China started?
When was the first of the Geneva Conventions on the treatment of war victims adopted?
When was the Fourth Crusade diverted from the Holy Land to Constantinople?
When was the last Bulgarian noble surrendered to the Byzantine Empire?
When was the Opium war held between Britain and China ?
When was the Ottonian dynasty replaced by the Salian dynasty?
When was the Treaty of Versailles signed?
When was the Tripartite Pact signed?
When were ancient Olympic games held first?
When were concave spectacles invented?
