HUNES
In world War 1 the British, and the French among others, were fighting against the so called "Central Powers" - German Empire, Austro-Hungarian Empire, Bulgaria and the Ottoman Empire.
The strong roman empire defeated it's enemy bravely and strongly
Germany, the Austro-Hungarian Empire and the Ottoman Empire.Germany
A redress of grievances against the British Empire
Principally Germany, Austria-Hungary and the Ottoman Empire.
The Ottoman empire was one of the Central Powers during WW1, thus is was fighting against the UK, France, Russia and their allies.
A league of a couple of dozen Greek city-states led by Sparta against the Persian Empire.
Australia fought with Great Britain and her ally the USA. They fought against the Japanese Empire and Nazi Germany but the majority of Australia's fighting was based in the Pacific.
By Fighting for the empire in harsh Battles.
It was the Persian Empire.
In World War 1, the German Empire, the Hapsburg Empire (Austria-Hungary), and the Turkish Empire, were joined along with some lesser allies against the British Empire, the French Republic, the Russian Empire, Italy, some lesser allies, and, eventually, the United States.
America fought the British Empire for independance in 1775-9.