Throwing one’s political opponent in jail has a long history to it, especially in countries where democratic principles struggle to take hold. The fate of Egypt’s Mohamed Morsi, who went from directly elected president to now languish in jail, is one high-profile contemporary example. But there are plenty of others, often in countries that are notional democracies.

One of the striking things about the recent US election was all the talk from the Trump camp about imprisoning Hillary Clinton. It is the first time that I remember such a dark threat being thrown around in the discourse of a modern western election. Trump has now said that he won’t pursue Clinton over handling of her email – despite the campaign-trail chant to “lock her up”. Still, there has also been speculation as to whether Trump himself will have to endure an impeachment process conducted by his political opponents, who are desperate to limit his time in office. Talk of getting rid of one’s political enemies is in vogue, it seems.

There are some interesting parallels to all of this in the political landscape of ancient Athens. It was here that the institution of ostracism was enacted in the 5th century BC – a word which we often use in a broad sense today, but not usually in formal political discourse. To be “ostracised” in classical Athens was to be exiled from the city for a period of 10 years. It was a part of the annual democratic processes of Athens, and therefore not as capricious as it tends to be in most other political contexts.

Ostracism worked like this. Each year the assembly of citizens (“ekklesia”) decided whether to hold an ostracism or not. If they agreed to do so, the process would commence shortly afterwards. It was like an election in reverse, a contest in unpopularity that no one really wanted to win.

If the decision was made to conduct an ostracism, citizens had the opportunity to write the name of the person they wanted to ostracise on an ostrakon (that is, a fragment of pottery suitable for writing on). The ancient evidence is somewhat contradictory, but it seems that if there were 6,000 votes cast in the ballot, then the person with the highest number of votes was exiled from Athens for ten years. They had ten days to pack their bags and go.

One such unlucky winner was Aristides the Just, an aristocratic statesman and renowned general. The biographer Plutarch recounts a story of his ostracism (which is probably fanciful, but a good yarn nonetheless):

Now at the time of which I was speaking, as the voters were inscribing their ostraka, it is said that an unlettered and utterly boorish fellow handed his ostrakon to Aristides, and asked him to write ‘Aristides’ on it. He, astonished, asked the man what possible wrong Aristides had done him. ‘None whatever,’ was the answer, ‘I don’t even know the fellow, but I am tired of hearing him everywhere called 'The Just.“ On hearing this, Aristides made no answer, but wrote his name on the ostrakon and handed it back.

All of this this might sound rather harsh on individuals who had decided to offer themselves for public service for the benefit of the city. A contemporary Athenian, however, would probably have found it very responsible and civilised. After all, an ostracised leader was allowed to keep his citizenship and property. And at the end of the ten years he could return and live in Athens again, much as he might have done if he had never been ostracised in the first place.

Moreover, the city could recall someone from exile prior to the end of the ten years, if they felt the need to do so. This actually happened in some renowned cases, as in the case of Aristides during the Persian wars.

Ancient Agora Museum in Athens. , CC BY-SA

More importantly, ostracism was established as part of the annual fabric of Athenian political life, not a ferocious descent into violent party politics. Nonetheless, it could be brutal, and all sorts of skulduggery probably took place to get rid of particular individuals.

One modern archaeological encounter was 190 ostraka found in a well at Athens with the name "Themistocles” written on them. These were probably a version of modern how-to-vote cards, written by a small number of people, and presumably organised by the enemies of Themistocles. An illiterate citizen would not even have had to trouble himself with scrawling the name himself. Just take an ostrakon and move on.

Themistocles, as it happens, was eventually ostracised at the end of the 470s BC, although he probably survived earlier attempts to get rid of him. When one bears in mind that Themistocles was the great champion of Athens (and Greece) in the sea-battle of Salamis against the Persians a short time beforehand (480BC), it is an indication that anyone could really fall victim to ostracism.

Others included Xanthippus, the father of Pericles, also Kimon, the prominent and wealthy political leader, and Thucydides the historian. And there were many others. Exile was a fundamental part of political life, and it was used by the people both as a rejection of particular policy positions, or for more specifically vindictive personal reasons. There was no single reason why Athenian citizens were ostracised.

Odd though it seems to us today, ostracism might be seen as a rather inspired way for a democratic polis (“city-state”) to keep tyranny at bay. In that sense it was successful at Athens, although the institution of ostracism probably didn’t last much much beyond 417BC.

Apart from anything else, ostracism reminds us that intolerance and vindictiveness have an ancient history to them. The Athenian system, at least, had the virtue of recognising that exile could be a part of the normal democratic processes, and could therefore take place in a way that would not severely damage the state.