I would have guessed an old german 9 Pfennig piece like this one: https://en.numista.com/catalogue/pieces106168.html
Gwalior - 1/4 Anna - 1917 - Maharaja Madho Rao Scindia [ATTACH]
1917: Norway - 1 Krone - 1917 - King Haakon VII. [ATTACH]
Austria-Hungary - Bravery Medal - 1917/18 - Emperor Karl I. [ATTACH]
Youre right and thats an interesting poster, I wonder how it would looks like if you add the landmass of the other countries colonies ;)
First hint: Its from a small european country (But not a city state)
Kingdom of Poland - 20 Fenigow - 1918 [ATTACH]
Ok next one: [ATTACH]
Kingdom of Bavaria - Medal - Golden wedding of King Ludwig III. [ATTACH] The medal was ment to be given to the soldiers on christmas but never...
1 Crown - Bermuda - 1959? https://en.numista.com/catalogue/pieces14207.html
1918: The empire is back! German Empire - 1/2 Mark - 1918 - Emperor Wilhelm II. [ATTACH]
Strait Settlements - 1 Cent - 1919 - King George V. [ATTACH]
1919: Germany - 5 Pfennig - 1919 [ATTACH]
Italy - The Commemorative Medal for the Italo-Austian War 1915-1918 - Instituted 1920 - Made from enemy bronze [ATTACH]
Great to see that the poor old Maximus gets relieved from some heinous historical accusations :) Anyway here my only coinage example I have from...
1920: Germany (City of Aachen) - 2 Mark (Notgeld) - 1920 [ATTACH]
Ok lets abandon this one [ATTACH] [ATTACH] - may the next one who likes to do so post another coin
Hmm... maybe a bit too hard? I'll give you another part of the coin: [ATTACH]
Next hint: The issuing country is still ruled by a Queen today.
Ok first little hint: Its a european coin
Separate names with a comma.