In a retrospective study on the city of Zurich published in January 2022, Mathias Lerch refined his method of analyzing demographics by expanding the scope of his study to the end of the 18th century. The city's online statistical directories were a gold mine of information that immersed him in the history and economic success of what is still the largest city in Switzerland. Lerch, the director of EPFL’s Laboratory of Urban Demography, underscores the need to create better tools to understand today’s urban growth in developing countries. “The role of international migration is often neglected in demographic studies,” he says.
Lerch focused his research on the years 1836 to 1949 and came away with some surprising insights. By studying Zurich’s fertility rate, population movements and the nationality of the city’s new residents, Lerch noted that, in the 19th century, families were having very few children on average. This prevented the population from renewing naturally, as deaths outnumbered births. He concluded that the city must have grown at that time through migration.
However, the rural exodus towards Zurich was not as significant as expected. “Between 1850 and 1900, the archives show that Swiss farmers leaving their land were headed more toward the New World than toward Swiss cities,” says Lerch. “These families wanted to continue farming, and many of those from the cantons surrounding Zurich were Catholic. They weren’t drawn to Zurich which, in addition to being Protestant, seemed unhealthy and offered difficult working conditions.”
Skilled workers and refugees
International immigration made up for the natural urban growth deficit and the loss of potential rural migrants, who opted for the New World, until the end of the 19th century. “We see skilled workers arriving from southern Germany, who had been replaced by machines in their region but who were highly sought after in Switzerland, where industrialization had just begun,” says Lerch. “We also find many French revolutionaries fleeing the Restoration.”
The city’s total growth remained low until 1850 but then rose to over 2% per year. It peaked at 8% at the end of the century, thanks largely to international immigration, with Italian workers helping pick up the slack from German workers. The proportion of Swiss citizens in the city’s population declined from 89% in 1836 to 78% in 1888.
Zurich Paradeplatz in 1946. © Macher Ludwig
By the early 20th century, however, Swiss society was changing. Literacy had become compulsory in 1874, the country was increasingly secular, and urban living conditions were improving (public lighting, sanitary infrastructure, hygiene, leisure activities, etc.). In addition, immigration restrictions were enacted in the United States. As a result, more rural Swiss people who gave up farming went to Zurich, with a peak influx in the 1920s. International immigration itself slowed with advent of nation-states, the introduction of passports in Europe, and the two world wars. After the Second World War, however, foreign workers came flooding back, giving Zurich an economic boost.
From Zurich to Addis Ababa
“If we know how a city grows, we can map out its future development, including the number of schools and any additional infrastructure that will be needed,” says Lerch. The demographer predicts that sub-Saharan cities will follow the same path that Zurich did. “In Addis Ababa, the capital of Ethiopia, the fertility rate has declined rapidly to two children per woman. Eventually, these cities will be dependent on migrants to renew their population, much like Zurich was.”