Guglielmo Barone and Sauro Mocetti compared tax data from the Tuscan city in 1427 and 2011, and the results of their study show that Florentines whose ancestors were rich during the Renaissance are likely to still be well-off today.
They analysed the data for family 'dynasties', identified by surname, and found that the profession and income of one's ancestors can help predict the profession and income of their living descendants.
Some 900 surnames present on the 1427 census are still present in Florence today, and the authors argue that, while not all those with a particular surname would be direct descendants of that family, the regional and distinctive nature of Italian surnames makes them a good predictor.
These results suggest a low level of social mobility, which is measured by "intergenerational elasticity", defined as the correlation between a parent and their adult child's socioeconomic status.
In Italy, this elasticity is estimated at around 0.5, a similar figure to the UK and US, and much higher than Scandinavian countries where estimates put elasticity at less than 0.2, meaning that your wealth bears a much lower correlation to that of your parents.
The tax data showed that not only can surnames be a predictor of wealth, but also of occupation, so that if your 15th century ancestor was a lawyer, it's more likely that you would be a lawyer today. Back in the 15th century, the top-earners were lawyers or members of the shoe-makers', wool and silk guild, while low-earners worked in professions such as sewing and sorting wool.
In their study, which challenges previous ideas that economic advantages do not usually last for more than three generations, Barone and Mocetti say they have proved "the existence of a glass floor that protects the descendants of the upper-class from falling down the economic ladder."
Their findings did not just relate to the elite one percent, where castles and estates could account for a large part of inherited wealth, but to the wider upper class; descendants of the wealthiest 33 percent of families in 1427 were likely to have above-average wealth in 2011.
They added that societies where wealth is retained within families to such an extent are not only likely to be viewed as "unfair", but may also be inefficient and less productive than societies where social mobility is more possible.
A society where wealth is passed on through generations "may also be less efficient as they waste the skills of those coming from disadvantaged backgrounds," said the study's authors.
It is particularly surprising that the richest Florentine families managed to maintain their wealth through 600 years of political and social upheaval; sieges and occupations, the change from a capital of a city-state to a city within a Republic, Benito Mussolini's Fascist regime and Nazi occupation, the post-war economic miracle.
The study's authors argued that, because there is no reason why Florence should be an exception, their results could be "thoughtfully extended to other advanced countries of western Europe".