2017: North Korea conducts its sixth and most powerful nuclear test
2016: The US and China, together responsible for 40% of the world's carbon emissions, both formally joined the Paris global climate agreement.
2001: In Belfast, Protestant loyalists begin a picket of Holy Cross, a Catholic primary school for girls. For the next 11 weeks, riot police escort the schoolchildren and their parents through hundreds of protesters, some of whom hurl missiles and abuse. The protest sparks fierce rioting and grabs world headlines.
1939: World War II: The United Kingdom and France begin a naval blockade of Germany that lasts until the end of the war. This also marks the beginning of the Battle of the Atlantic.
1939: World War II: France, the United Kingdom, New Zealand and Australia declare war on Germany after the invasion of Poland, forming the Allies.
1935: Sir Malcolm Campbell reaches a speed of 304.331 miles per hour on the Bonneville Salt Flats in Utah, becoming the first person to drive an automobile over 300 mph.
1925: USS Shenandoah, the United States' first American-built rigid airship, was destroyed in a squall line over Noble County, Ohio. Fourteen of her 42-man crew perished, including her commander, Zachary Lansdowne.
1916: World War I: Leefe Robinson destroys the German airship Schütte-Lanz SL 11 over Cuffley, north of London; the first German airship to be shot down on British soil.