Populism is sexy. Particularly since 2016 – the year of the Brexit referendum and the election of Donald Trump – it seems as if journalists just cannot get enough of it. In 1998, the Guardian published about 300 articles that included the terms “populism” or “populist”. In 2015, these terms were used in about 1,000 articles, and one year later this number had doubled to almost 2,000.

The increasing popularity of the term is no coincidence. Populist parties have tripled their vote in Europe over the past 20 years. They are in government in 11 European countries. More than a quarter of Europeans voted populist in their last elections.

Why? There is no easy answer to this question. Recent academic studies have shown that throughout the western world populist attitudes are widespread. Many citizens take the view that ordinary, virtuous people have been betrayed, neglected or exploited by a corrupt elite. Although citizens with strong populist attitudes do not necessarily vote for a populist party (in fact, many of them don’t), there are various circumstances that increase the likelihood that they will do so.

Firstly, when a society is more individualised, and voters are more independent and emancipated, electoral volatility tends to be higher. Such circumstances will enhance the probability that populist attitudes are translated into real populist votes. After all, without a certain degree of detachment from traditional mainstream parties, voters are unlikely to actually switch away from them and turn to populists.

Secondly, there is a fertile breeding ground for populists when mainstream left and right parties converge ideologically. If this is the case, many voters will be susceptible to the message that mainstream political parties are all one and the same. A good example is how in France the Front National (now National Rally) merged the names of the centre-right UMP and the centre-left PS into “UMPS” in its campaigning – the political equivalent of Tweedledum and Tweedledee. Moreover, when mainstream parties converge, they leave fallow a lot of ideological space, and therefore tend to be unresponsive to the worries of more radical citizens.

Thirdly, crises can make the activation of populist attitudes more likely. A financial crisis, for instance, makes mainstream parties highly vulnerable to the critique that “the established elite” has messed things up. The European refugee crisis provided populist parties with ammunition for the argument that governing elites had opened up the borders and were unable to deal with the inflow of immigrants.

Fourthly, widespread corruption plays straight into populist hands. If it turns out that political parties are highly corrupt, the populist claim that people are exploited by an inward-looking, condescending elite will find wide public support. This is exactly what happened in Italy in the early 1990s, for instance. As a result of a nationwide judicial investigation into bribery, nepotism and other forms of corruption, the whole party system was turned upside down. This cleared the way for the rise of populists such as Silvio Berlusconi and the League.

Yet a fertile breeding ground for populism is not enough for populism to thrive. There should also be a credible populist challenger who offers an attractive alternative to the existing parties. In order to be perceived as an attractive alternative, a challenger party needs to express a message that appeals to large numbers of discontented voters. Moreover, what also helps is an alluring leader and, especially in the long term, a well-functioning party organisation.

The changing media environment also plays a role. Because of dwindling subscription rates, traditional media increasingly focus on topics they expect to sell well, such as scandals and conflict, fuelling the sense of crisis that populists can draw on.

Of course, sociopolitical contexts vary by geography – and so does populism. In northern Europe, successful populists are mainly radical rightwing populists. Parties such as the Danish People’s party, the Finns and the Sweden Democrats all combine a xenophobic nationalist outlook with a populist message. Leftwing populism is much less widespread in this part of Europe – possibly because the strong economies and generous welfare systems of the Nordic countries make a radical leftwing populist message less pressing.

Southern Europe looks different. In countries such as Spain, Italy and Greece, populism is not exclusively a radical rightwing phenomenon. This might well be due to the fact that the financial crisis hit these countries harder than most. They therefore form the perfect setting for a leftwing populist message. Parties like Podemos in Spain and Syriza in Greece combine their populism with a radical leftwing main ideology. In Italy, the Five Star Movement combines populism with a diverse array of ideological stances.

Western Europe differs from southern Europe in that radical leftwing populists are less successful. This is most likely due to the fact that countries in this part of Europe have much stronger economies than their southern European neighbours. The exception that proves the rule is Ireland. This country did not perform very well economically and harbours a relatively successful radical leftwing populist party: Sinn Féin.

The landscapes in central and eastern European countries look very different. Here, populism generally did not bob up at the fringes of the political spectrum, but in the centre. Parties such as Fidesz in Hungary and Law and Justice in Poland started their political lives as mainstream parties. Only later on did they also embrace populism and, even later, nativism. It is probably because these do not have radical heritages – which could potentially thwart their “respectable” images – that they have managed to become the leading parties in their respective countries.

Despite all these geographical differences, throughout Europe the breeding ground for populism has become increasingly fertile. And populist parties are ever more capable of reaping the rewards.