New 1914

In this alternate reality, the great nations of antiquity never fell and now find themselves in 1914 with weaponry and equipment appropriate to that year (i.e., rifles, machine guns, modern artillery, ships, including the first armored vehicles and airplanes—in other words, all the weaponry used between 1914 and 1918). The main factions are:
The Roman Empire: a large amount of military and human resources but many enemies, political intrigue and corruption dominate (they control Italy, Gaul, Hispania and there are guerrilla wars in Carthage and Africa)

The Greek Confederation: After the rise of Rome as a power, the Greek city-states united in a confederation. They were well-equipped, but due to mistrust, the confederation was on the verge of disintegration (they controlled Greece, the Aegean islands, Macedonia, and Illyria).

Persian Empire: The great Persian Empire, ruled by Darius in 28 AD, thanks to the rich trade routes of the East, can maintain huge and well-equipped armies with rifles and grenades, but not with such good training. The easternmost satrapies, such as Sogdia and Bactria, are on the verge of rebellion (they control Anatolia, Egypt, Syria, and all of the East up to the Hindu Kush mountains).

The Germanic tribes: fierce warriors from east of the Rhine are not very well equipped since they mostly use muskets and flintlock cannons; all the modern weaponry they have is from looting from Rome and Greece. They are countless divided tribes that could unite and form a great empire (basically they control all of northern Europe including Dacia).