From Percy Jackson to God of War to Hadestown, the Greek gods and the myths surrounding them fascinate and entertain modern readers, despite these stories being thousands of years old. But why do these stories only exist in works of fiction? Why are the Greek gods no longer formally worshiped?
The Greek gods are no longer worshipped because the spread of Christianity made the worship of pagan gods illegal. As Christianity spread through Europe, Greek and Roman polytheism became less and less popular. Eventually, paganism was outlawed completely.
Several factors led to the fall of the old Greek belief system, including natural disasters, the conversion of influential politicians, and more. This article will examine the decline of Greek paganism, what replaced it, and how the religion is practiced today.
Also see Why Are Greek Gods Flawed? to learn more.

When Did People Stop Worshiping Greek Gods?
The exact end of the Ancient Greek religion is difficult to pinpoint. When the Roman Empire absorbed the Greek religion, the Greeks continued to worship their gods. The Romans merely gave the gods new names and slight changes.
People stopped worshiping the Greek and Roman gods by 800 A.D., as worship of most pagan gods was illegal by then. However, people stopped worshiping the Greek gods by their Greek names almost a thousand years earlier, when the Romans overtook the Greeks.
When the Romans conquered Greece in the 2nd century B.C., the Greek gods became part of the Roman pantheon. [1] Greek gods were combined with Roman equivalents, such as Zeus with Jupiter and Athena with Minerva. Because the Romans absorbed new religions instead of outlawing them, the Greeks gods were worshiped long after the Greeks were conquered.
Greco-Roman polytheism continued for several centuries, declining slowly. As Christianity spread throughout Europe, the Greek and Roman gods fell in popularity. In the 4th century A.D., the Christian emperor Theodosius I began persecuting pagans.
There were only a few groups of Greek pagans in Europe by the Middle Ages. The last worshippers of the Greek gods were on the Mani Peninsula of Greece around 800 A.D.
Also see Why Did Greek Gods Marry Their Siblings? to learn more.

What Replaced the Worship of Greek Gods?
Some scholars theorize that the old pagan religions became less popular as they grew. The Romans often absorbed other religions into their own (including the Greek gods), and the religion eventually grew unsustainably big.
The same is true for when people stopped worshiping the Greek gods; they didn’t become atheists who rejected all religions. Rather, they typically changed religions, either voluntarily or under the threat of law.
For example, the Romans didn’t outlaw the Greek gods when they conquered Greece. They added the Greek gods to the Roman religion, effectively changing Greek paganism into Roman paganism.
Roman gods first replaced the worship of Greek gods, though there were very few changes between the Greek and Roman religions. Greco-Roman paganism was later replaced by Christianity, which didn’t tolerate the worship of multiple gods.
The Greeks didn’t proselytize or try to convert others to their religion. [2] The ancient Greek religion was decentralized, with no single text or teachings. The Greek religion could peacefully coexist with other religions. Greco-Roman pagans were willing to add the Christian god to their pantheon.
But Christianity was unable to coexist with Greco-Roman paganism. Christians only recognized one God and believed the pagan pantheon was entirely false. They taught their beliefs were the only true ones and needed to share this truth with others. This desire to convert pagans and the refusal to recognize other gods led Christianity to overtake paganism as the dominant religion.
Also see Did Greek Gods Have Last Names? to learn more.

Do Modern Greeks Still Believe in Greek Gods?
For almost two thousand years, Greece has been a predominantly Christian nation. Until recently, the only legally recognized religions were Christianity, Judaism, and Islam. However, there’s a growing movement of Greek pagans revisiting the old religion.
A few thousand modern Greeks still worship the Greek gods. [3] These worshippers are known as Greek pagans or Hellenes, and they believe in reviving their culture’s pre-Christian religion. Most Hellenes don’t believe that the Greek gods are literal, though.
They consider the gods representations of ideas such as wisdom and beauty, not supernatural humanoids sitting on a mountain. Hellenism is more about connecting with the ancient Greeks than worshiping literal gods.
One major Hellenist holiday is Prometheia, a festival that’s unique to the new religion and didn’t exist in ancient Greece. The festival honors Prometheus, a minor Titan who stole fire from the gods and gave it to mankind.
The gods punished Prometheus for his treachery, but the damage was done. Humans had the fire, which allowed them to advance as a species.
Prometheia is an opportunity for Hellenes to gather as a community and celebrate their commitment to this new religion. Some followers dress in modern clothes, while others wear tunics, armor, and other clothes reminiscent of the ancient past.
They celebrate nature, their shared heritage, and their ancestors. They pray together, choose ancient names that honor the gods, and even perform marriages.
But even though the religion emphasizes connecting with Greece’s past, the ancient Greeks did not celebrate Prometheia. Prometheus was a minor figure in mythology. He’s not one of the twelve Olympian gods that the Hellenes purport to worship.
However, the Hellenes legally can’t worship the same way their ancestors did. Any surviving Greek temples are protected spaces, and the Hellenes are not permitted to use them for their original intended purpose. The Hellenes plan to build a new temple in Athens, though this hasn’t yet come to fruition.
Hellenism is more about rejecting Christianity than revering the Greek gods. It’s a reclamation of Greece’s pre-Christian past and a way to fight against over a thousand years of Christian rule.
Because the religion is so decentralized, there’s no way to know how many of the practitioners truly worship the Greek gods and how many simply want to connect with their pre-Christian ancestors.
Conclusion
The ancient Greek religion fell to the Romans and Christianity, but it’s being revived and refreshed today by modern Hellenism.
Also see Why Are Greek Gods Depicted As White? to learn more.