When did people stop worshipping the Greek gods?

When the Roman Empire conquered the ancient Greek Empire. However, the Romans assimilated Greek culture into their own, and continued to worship a different "version" of the Greek gods.

For example, the Romans took the Greek god of love Eros and named him Cupid. They changed Zeus to Jupiter, Aries to Mars, Aphrodite to Venus, Hermes to Mercury, Hades to Pluto, Poseidon to Neptune, Artemis to Diana, and so forth, and so forth.

People stopped worshipping the Roman gods around the time the Roman Empire split in two and collapsed. Christianity then took its place, leading to the creation of the Holy Roman Empire.

The Christian Church became the state religion of the Roman Empire in the 380s, after which worship at pagan temples was outlawed in 391. The Christian Churches expropriated the property of the temples and began to persecute those who continued to worship their old gods. Nevertheless, private worship of the Greek and Roman gods continued for perhaps another two centuries.