Pretty much what it says in the title: At which point were the first and second world war labelled as world wars? Which events caused this? And who started using this term, did it come from politicians, journalists, or someone else entirely?
The first reference to the Great War as World War I comes from General Charles A Court Repington in a diary entry, dated 10th September 1918, in which he described a meeting where the attendees were deciding what historians would call the conflict. He wrote and I quote 'Finally, we mutually decided to call it the First World War in order to prevent the millennium folk from forgetting the history of the world was the history of war'.
(Which makes me wonder what other names were on the list)
World War II received it's name from Time Magazine on September 11th 1939 in the following extract which describes the German invasion of Poland.
"World War II began last week at 5:20 a. m. (Polish time) Friday, September 1, when a German bombing plane dropped a projectile on Puck, fishing village and air base in the armpit of the Hel Peninsula",