In the summer of 1762, the Russian Empire witnessed a royal reversal so rapid that it would cast a shadow over Catherine the Great’s reign for the rest of her life.

Peter III had been emperor for only about six months when his own wife moved against him.

Catherine—born a minor German princess and brought to Russia as a teenager to marry the future emperor—secured the backing of powerful officers, especially within the elite Guards regiments. On June 28 according to the Russian calendar then in use, corresponding to July 9 in the modern Gregorian calendar, she was proclaimed sovereign in St. Petersburg. Peter’s support collapsed, and he signed an abdication.

The 34-year-old former emperor was taken into custody at Ropsha, a country estate outside St. Petersburg.

He would never leave alive.

Eight days after Catherine’s coup, Peter was dead.

The official explanation attributed his death to illness. But almost immediately, another version circulated: the deposed emperor had been killed by the men guarding him.

Among those closest to the mystery was Alexei Orlov, brother of Catherine’s lover and political ally Grigory Orlov. Alexei had helped bring Catherine to St. Petersburg during the coup and was subsequently involved in guarding Peter at Ropsha. Later accounts linked him directly to the former emperor’s violent death.

Yet the question that has followed Catherine for more than 260 years is more difficult than simply asking whether Peter was murdered.

Did Catherine order it?

There is no conclusive evidence that she did.

And that uncertainty is what makes Peter III’s death so important. Catherine unquestionably participated in overthrowing him. Men closely connected to her coup were with him during his final captivity. His death unquestionably made her political position safer.

But political benefit is not proof of a murder order.

To understand why Peter ended up dead at Ropsha—and why Catherine could never completely escape suspicion—it is necessary to return to the extraordinary six months in which a deeply unpopular emperor, an ambitious wife, several Guards regiments and the Orlov brothers transformed the Russian monarchy.

Catherine Had Not Been Born to Rule Russia

The woman history remembers as Catherine the Great began life as Sophie Friederike Auguste of Anhalt-Zerbst.

She was born in 1729 in Stettin, then part of Prussia, into a relatively minor German princely family.

Her path to Russia opened because Empress Elizabeth needed a suitable bride for her nephew and heir, Peter.

Sophie traveled to Russia as a teenager, converted to Russian Orthodoxy and received a new name: Catherine Alexeyevna.

In 1745, she married Peter.

The marriage was disastrous.

Later descriptions of their relationship are complicated by the fact that Catherine herself left memoirs portraying Peter in extremely unfavorable terms. Her account cannot be treated as a neutral description of the husband she eventually overthrew.

But the estrangement between them is not seriously disputed.

Both developed relationships outside the marriage. Peter became openly attached to Elizabeth Vorontsova. Catherine had several relationships of her own.

One of the most important was with Grigory Orlov.

Grigory was a Guards officer from a family of five brothers. By the early 1760s he had become Catherine’s lover, and his connections within the military would prove enormously important. Catherine secretly gave birth to their son Alexei Bobrinsky in April 1762—while she was still married to the reigning emperor.

By then, the political situation had become dangerous.

Empress Elizabeth had died in January 1762 by the Gregorian calendar.

Peter became Emperor Peter III.

Catherine became empress consort.

But there was little reason to assume her position was secure.

Peter III Made Enemies Remarkably Quickly

Peter’s reign lasted only about six months, which makes sweeping judgments about what kind of ruler he might have become difficult.

Some of his policies were significant and potentially reforming. Most notably, his government issued a manifesto freeing the Russian nobility from compulsory state service.

But other decisions alienated politically crucial groups.

The most famous concerned Prussia.