Whether it’s the caricature of the introverted English, the brash Americans or the industrious Japanese, national stereotypes are easy to come by. But do countries really have their own distinct personalities?

When psychologists have given the same personality test to hundreds or thousands of people from different nations, they have indeed found that the average scores tend to come out differently across cultures. In other words, the average personality in one country often really is different from the average personality in another.

Crucially, these average differences in personality between nations are not the same as the stereotypes we hold. Although we tend to agree with each other about what the typical personality type is in a given country, including our own, the research suggests that our assumptions are often wide of the mark.

Several large international studies have now documented cross-cultural differences in average personality. One of the most extensive was published in 2005 by Robert McCrae and 79 collaborators around the world, who profiled more than 12,000 college students from 51 cultures. Based on averaging these personality profiles, the researchers were able to present an “aggregate” trait score for each of the cultures.

Brazilians, French Swiss and the Maltese scored highest on measures of Extraversion, while the lowest scoring were Nigerians, Moroccans and Indonesians

The highest scoring cultural groups for Extraversion on average were Brazilians, French Swiss and the Maltese, while the lowest scoring were Nigerians, Moroccans and Indonesians. The highest scoring for Openness to Experience were German-speaking Swiss, Danes and Germans, while the lowest scoring on average were Hong Kong Chinese, Northern Irish and Kuwaitis. The study also uncovered variation between countries in the three other main personality traits of Neuroticism, Conscientiousness and Agreeableness.

Of course, it’s important to remember that these are averages and there is a lot of overlap between countries; there are undoubtedly a lot of people in Indonesia who are more extraverted than some from Brazil. There are also complications and controversies around how to interpret these kind of results, such as the huge challenge of ensuring that personality questionnaires are translated to mean exactly the same thing to participants in all the different cultures, and that the samples in each culture are truly representative of that culture. Last year, Katherine Corker at Kenyon College and colleagues demonstrated that small but non-trivial differences in the average personality scores between students at different US universities, thus showing the risks of inferring too much about an entire country from a single sample.

Critics of this field also point out issues like how much citizens of different countries are disposed to tick extreme scores on a psychological test (although McCrae and his collaborators did address some of these concerns, for example by including a measure of “acquiescence” – people’s tendency to agree with survey items).

Despite these methodological challenges, several large studies have repeatedly uncovered variation in average personality across the globe, and the results usually chime in theoretically consistent ways with other measures – countries that score higher in Extraversion, for example, also tend to score higher in average levels of self-esteem. International studies of personality have also shown that while average trait levels vary between cultures, the basic structure of personality, organised into five main traits, seems to be a universal.

Consider another huge study of cross-cultural personality differences, led by David Schmitt at Bradley University and published in 2007, that involved over 17,000 people from 56 different nations around the world. Again, between-nation variation emerged in average personality. For example, the highest average scores for trait Neuroticism were found in Japan and Argentina while the lowest were found in the Democratic Republic of the Congo and Slovenia. Meanwhile, the highest scoring nations for Agreeableness, on average, were the Democratic Republic of the Congo and Jordan, while Japan and Lithuania scored the lowest.

People in Africa tended to score higher on trait Conscientiousness than people from all other world regions

This study also looked at similarities in average personality across supra-national regions, finding for example, that people in Africa tended to score higher on trait Conscientiousness than people from all other world regions, while people in East Asia tended to score lower.

But while differences in personality do exist between cultures and nations, they often don’t match up with the widely held stereotypes of national character. You probably have an idea in your head of what the average personality profile is of people from the various cultures that you’re familiar with. Take the trait of Extraversion. Here in the UK most of us would probably say that the average English person is far more reserved than the average American. But these kinds of national personality stereotypes are rarely accurate (in fact, the 51-culture study described above found that average Extraversion was higher in England than in the USA; the 56-culture study found that Americans edged it, but with very little difference between the two countries).

Early in the 2000s, in one of the first comparisons of national stereotypes with real national personality differences, Robert McCrae tested the assumptions about national personality held by a group of people who arguably ought to know better than most: experts in cross-cultural psychology. McCrae presented a panel of eight of these experts with a list of 26 different world cultures for which he had average personality data. Then for each of each of the five main personality traits, McCrae asked the experts to organise the cultures into lists according to the seven highest- and lowest-scoring. The experts’ performance was woeful. Compared with the actual personality data, the experts performed no better than if they had simply been guessing.

The rest of us seem to fare no better. In 2005, Antonio Terracciano and his colleagues asked nearly 4,000 participants, mostly college students, from 49 cultures across six continents to estimate the average personality profile of a person from their own culture. Once again, the participants’ idea of the typical personality type in their country did not match their country’s actual personality profile. A more recent study published in 2013 involving over 3,000 participants in 26 nations came to a similar conclusion.

An isolated population is likely to become more introverted and inward focused through the generations as bolder individuals are more likely to choose to emigrate

What could explain these national differences in average personality? The reasons are likely partly genetic, perhaps to do with historic migration patterns. For example, people strong on traits related to risk-taking and openness might be more likely to migrate, so these traits are likely to be over-represented in regions that were historically on the frontier of exploration; conversely, an isolated population is likely to become more introverted and inward focused through the generations as bolder individuals are more likely to choose to emigrate.

A recent series of studies conducted with islanders resident in several isolated Italian archipelagos put these principles to the test. Andrea Ciani at the University of Padova and his colleagues found that islanders are less extraverted and open-minded, but more conscientious and emotionally stable, than their mainland neighbours located 10 to 40 miles away. This is likely because, over time, bolder more open-minded individuals have chosen to emigrate away from the islands.

Supporting this, a sample of recent emigrants from the islands to the mainland were found to score higher on extraversion and openness than the remaining islanders. Ciani's team also genotyped a sample of islanders and mainlanders and found that a version of a gene previously associated with risk-taking (the 2R allele of the DRD4 gene, which codes for a receptor for the neurotransmitter dopamine) was less common among islanders. The researchers said this suggests there is “some genetic basis for the observation that individuals in long-isolated communities exhibit a particular personality type”.

Undoubtedly environmental factors also play a part: for instance, there’s evidence that traits associated with extraversion and openness are lower in regions where risk of infection is greater, which makes evolutionary sense in terms of reducing the spread of disease. Experts have also speculated that differences in climate could influence regional differences in personality, such as cold regions with a lack of sunlight contributing to greater emotional instability.

Living in a crowded environment leads us to adopt a more future-oriented mindset, such as investing more in long-term relationships

Even population density could play a part. Recent evidence suggests that living in a crowded environment leads us to adopt a more future-oriented mindset, such as investing more in long-term relationships, perhaps in part as a way to deal with increased competition with other people; in other words, just the kind of approach you would associate with higher-trait conscientiousness.

Whatever the causes, once regional differences in personality are established, one possibility is that they may become self-perpetuating as there is evidence that people are drawn to live in areas occupied by others with similar character profiles to their own.

Given how important personality traits are to life outcomes at the individual level – from wellbeing to career success – this issue of national differences in personality is arguably more than a lively conversation topic for a dinner party. Any cross-cultural differences in trait levels at the national level might contribute to, or at least reflect, international differences in such things as wealth, happiness, corruption, innovation, and health. Higher-trait neuroticism, for example, is strongly associated with numerous negative health outcomes, including mental health diagnoses like anxiety and depression, but also chronic physical conditions like heart disease and dementia. It stands to reason that in countries where average trait neuroticism is higher, citizens will be more vulnerable to physical and mental ill health.

Personality differences around the world might even have contributed to the emergence of different political systems. Last year, Joan Barceló at Washington University in St Louis compared countries’ average personality trait levels with their political systems and found a correlation: countries with higher average trait Openness tended to have more democratic institutions, an association that held even after factoring out other relevant influences such as economic development. Although we can’t conclude that more of this personality trait in a national population causes democracy (the causal direction could flow the other way, for example), Barceló believes this is certainly plausible and that part of the reason is that open-minded citizens are more motivated by self-expression and less by traditional values. Her data seemed to back this up: differences in these motivations partly mediated the links between nations’ average trait levels and their political institutions. “Societal personality differences may play a larger role in predicting a country’s democracy than previously realized,” she said.

At the very least, the findings on international differences in personality could be another reason for us to question our assumptions about other countries’ attitudes and behaviours. As the personality psychologist Richard Robins commented in 2005, this line of research suggests that “in contrast to personality traits – which reflect actual differences in the way people think, feel and behave – stereotypes about national character seem to be social constructions designed to serve specific societal purposes.”

In other words, your views on other cultures may say more about yourself and your own society, than the patchwork of personalities that actually exists across the world.

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Dr Christian Jarrett edits the British Psychological Society's Research Digest blog. His next book, Personology, will be published in 2019.

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