Last week, Theresa May accused Russia of “meddling in elections” and trying to “undermine free societies”.

The remarks followed Donald Trump’s defence of Vladimir Putin, over claims that he interfered with the US presidential election last year.

“[Putin] said he didn’t meddle,” Mr. Trump told reporters. “Every time he sees me he says, ‘I didn’t do that,’ and I really believe that when he tells me that, he means it.”

One thing is certain, however: meddling in elections is nothing new. And Russia is not the only country to have been accused of it.

The west – and particularly the US – have a long history of rigging polls, supporting military coups, channeling funds and spreading political propaganda in other countries.

‘One in nine elections’

Dov Levin, an academic from the Institute for Politics and Strategy at Carnegie Mellon University, has calculated the vast scale of election interventions by both the US and Russia.

According to his research, there were 117 “partisan electoral interventions” between 1946 and 2000. That’s around one of every nine competitive elections held since Second World War.

The majority of these – almost 70 per cent – were cases of US interference.

And these are not all from the Cold War era; 21 such interventions took place between 1990 and 2000, of which 18 were by the US.

“60 different independent countries have been the targets of such interventions,” Levin’s writes. “The targets came from a large variety of sizes and populations, ranging from small states such as Iceland and Grenada to major powers such as West Germany, India, and Brazil.”

It’s important to note that these cases vary greatly – some simply involved steps to publicly support one candidate and undermine another.

But almost two thirds of interventions were done in secret, with voters having no idea that foreign powers were actively trying to influence the results.

Levin told FactCheck he was surprised by how common US election interference was. “Such interventions can frequently have significant effects on election results in the intervened country, increasing the vote share of the assisted side by 3% on average – enough to determine the identity of the winner in many case.”

According to Levin’s research, those countries where secret tactics have been deployed by the US include: Guatemala, Brazil, El Salvador, Haiti, Panama, Israel, Lebanon, Iran, Greece, Italy, Malta, Slovakia, Romania, Bulgaria, Albania, Sri Lanka, the Philippines, South Vietnam and Japan.

For Russia, the list of covert interventions includes: France, Denmark, Italy, Greece, West Germany, Japan, India, Pakistan, Bangladesh, the Congo, Venezuela, Chile, Costa Rica, and the US.

Levin’s research points out that, historically, election meddling has actually been far more common than other methods of political intervention, like military invasions and coups.

US interference and meddling

Covert interventions have been done by many countries over the years and – because they are shrouded in secrecy – it’s impossible to get a comprehensive picture of every instance across the world.

Part of the reason why we know about lots of US operations is that its government is relatively transparent when compared to some others. (‘Relatively’ is the key word here: there is much we may never know about its secret foreign plots, but the release of many historical documents do allow us to shed some light – albeit usually years later).

One of the earliest examples of covert US interventions came with Italy’s 1948 election, when the CIA helped the Christian Democrats beat the Communist Party.

Nearly 50 years later, a former secret agent admitted: “We had bags of money that we delivered to selected politicians, to defray their political expenses, their campaign expenses, for posters, for pamphlets.”

The Washington Post has reported the CIA’s operation also included “forging documents to besmirch communist leaders via fabricated sex scandals,” and “spreading hysteria about a Russian takeover and the undermining of the Catholic Church”.

Over the years, many of America’s interventions have involved ploughing funds into their preferred candidate’s campaign.

For instance, throughout the 1950s and 60s, the US secretly financed the ruling Liberal Democratic Party in Japan, despite denials from party leaders. Former intelligence officials have said America’s aim was to undermine the Left and make Japan one of Asia’s most strongly anti-communist countries.

In the 1980s, an American official confirmed to the New York Times that “about $20,000” had been given to support Nicolas Barletta presidential campaign in Panama.

And, in 1990, $400,000 was given to organisations Czechoslovakia, which were leading the revolution against Communist rule, and which become political parties for the country’s first free elections in decades.

Funding was also provided for parties in Albania. According to reports, one US diplomat explained: “If Albania votes for socialism in this election, a lot of Western investors and governments are going to direct their aid elsewhere.”

Coup d’etats

All this is to say nothing of US-backed coups against democratically elected leaders.

For instance, in 2013 the CIA finally admitted it had been behind the coup against Iran’s secular prime minister, Mohammad Mosaddeq, which took place 60 years earlier.

Reports say that the UK persuaded President Eisenhower to take action after Mosaddeq nationalised the British Anglo-Iranian Oil Company, (later known as BP). The CIA duly planned to install a “pro-western government” in Iran.

An internal CIA document stated: “The military coup that overthrew Mosaddeq and his National Front cabinet was carried out under CIA direction as an act of US foreign policy, conceived and approved at the highest levels of government.”

It was a similar story in Guatemala, with the overthrow of President Jacobo Arbenz in 1954.

The New York Times has likened his personal politics to a “European-style democratic socialist”, but Arbenz’s reforms angered the American multinational United Fruit Company, which had huge landholdings in the Guatemala.

Declassified CIA documents reveal how it launched a huge $3m clandestine operation against the government, including “attempts to subvert and or defect Army and political leaders, broad scale psychological warfare and paramilitary actions”.

They trained military groups and set up a “clandestine broadcasting station” which aired anti-communist propaganda designed to “intimidate” public officials.

Secret agents also made up fake reports claiming that the Soviet Union was sending submarines full of weapons to help arm the Arbenz regime. (Eventually a real shipment did materialise).

The CIA itself justified action citing Arbenz’s “communist influence and a hardening anti-U.S. policy”.

More recent interventions

Reports of American interference in other countries is not confined to Cold War history. But with more recent cases, there is generally less evidence available because secret documents have yet to be declassified.

This means many of these incidents broadly remain allegations, without the detail to tell the full story.

The Honduran coup of 2009 saw President Zelya being “seized and, still in his pyjamas, hustled onto a plane to Costa Rica“.

The US refused to join other countries in declaring it as a “coup”, claiming that – if they did – “you immediately have to shut off all aid including humanitarian aid”.

What’s more, Secretary of State Hillary Clinton, said there were “very strong arguments” for the coup which had “followed the law”. And crucially – rather than calling for the democratically elected president’s return – America pushed for fresh elections.

Clinton later admitted developing plans to ensure “elections could be held quickly and legitimately, which would render the question of Zelya moot”.

There are also questions around America’s role in the Ukraine. After the country’s government made a trade policy u-turn, towards Russia rather than the west, Senator John McCain joined protesters in the capital. He said he was there “to support your just cause” and supported “a grassroots revolution”.

Later, a leaked phone conversation between the US Ambassador to Ukraine and the US Assistant Secretary of State hinted at extensive involvement. They spoke about the need to “midwife this thing” and said Arseniy Yatsenyuk was “the guy”, shortly before he became president.

The true extent to which America was actually involved in these cases may not be known for years.