100 Years Ago: The Locarno Treaties & the Hope for Lasting Peace

If you’re tracing your European family history through the 1920s and 1930s, you may have noticed something odd. Between roughly 1926 and 1930, there aren’t as many migration records to search through, meaning that there were a lot fewer families moving from place to place. Also, during this same period, there were more people buying houses and starting new businesses, showing that families tended to put down roots in places they liked. Then, we hit the mid-1930s, and everything changes again — sometimes dramatically. The Locarno Treaties explain why. A century ago, diplomats met in London to sign agreements created in Locarno, Switzerland. People called it the “Spirit of Locarno,” and at the time, it looked like Europe’s best chance to avoid another war. Here we look at why this matters when you’re researching family history in historical records.

Key facts on the Locarno treaties:

• The Locarno Treaties (1925) led to a period of stability that stretched from 1926 to 1930, which directly changed how people moved around across Europe.
• Germany’s readmission to the League of Nations after World War I and early troop withdrawals from the Rhineland affected millions of families in occupied territories.
• The treaties’ collapse in 1936 triggered new waves of migration as families recognized another war was coming.
• Understanding this period helps genealogists contextualize why ancestors stayed put or moved when they did.

What did the Locarno treaties actually do?

The Locarno Treaties consisted of 7 agreements that brought together Germany, France, Great Britain, Belgium, Italy, Poland, and Czechoslovakia. They guaranteed Germany’s western border with France and Belgium, and the Rhineland would stay demilitarized.

Everyone agreed to settle disputes through the League of Nations instead of sending in troops. What made Locarno different from Versailles was that it was voluntary. It wasn’t forced on Germany as punishment, with every country sitting down as equals.

Three men drove this: German Foreign Minister Gustav Stresemann, French Foreign Minister Aristide Briand, and British Foreign Secretary Austen Chamberlain. They’d later share the Nobel Peace Prize for their work.

How to trace your family through the Locarno period

The Locarno years left clear patterns in genealogy records, as families who’d been cautious about staying in place suddenly started making long-term commitments. It shows there was a genuine belief at the time that peace would hold. So, how do you go about using these records for your tree?

You should start with German records or French genealogy collections from 1926–1930 and remember to use MyHeritage’s SuperSearch™ function, as it lets you search across multiple record types at once. 

Here’s what you’re looking for:

• Property purchases spike around 1926–1928, especially in formerly occupied areas
• Business registrations pick up as people felt secure enough to invest
• Marriage records show couples who’d delayed suddenly tying the knot
• Census records show families staying at the same address instead of moving every few years
• Birth records increased as couples felt confident raising children in peacetime

Naturally, the pattern changed completely in the mid-1930s. Hitler violated the Locarno Treaties in 1936, and families could see that war was coming. 

This is usually most noticeable in the years before the start of the war, as both migration records and military service records were seen more often. Newspaper archives from 1936–1937 also capture the growing unease across Europe.

Want to trace your ancestors through the Locarno years?

The Locarno Treaties provided a short window during which European families believed peace would last. By looking at various record types from this era, you’ll get a better idea of the level of confidence they had in peacetime holding. It’s details like this that can really bring your family tree to life.

At MyHeritage, we give you a wide array of tools that help you find these patterns in your own family tree. Whether your ancestors stayed in the Rhineland during this period or they left when they saw what was coming, you’ll see how things played out.

So, why not give our tools a try? Start exploring today and discover what your family did during these pivotal years.

FAQs about the Locarno era and family history research

Why were the Locarno Treaties considered so significant?

Because they were actually negotiated, not dictated. Germany sat at the table as an equal, not as the defeated enemy forced to sign whatever was put in front of them. That made all the difference. 

What was the ‘Spirit of Locarno’?

It was more than politicians feeling good about themselves. Between 1925 and 1930, things actually got better. Military tensions dropped. Economies improved. People started believing you could solve international problems without sending in the army. 

For families living through it, it was some welcome breathing space between the chaos of World War I and what was coming in the 1930s. 

What records should I prioritize when researching ancestors from the Locarno period?

Start with census records from 1926 to 1930 to see if your family stayed put. Property purchases and marriage records from this window show families committing to their locations. For the post-1936 shift, focus on emigration records and local newspapers.

My ancestors emigrated in 1928. Were they fleeing danger?

Unlikely. 1928 sits right in the middle of the Locarno years, when things looked stable. Families leaving between 1926 and 1930 were probably seizing an opportunity rather than running from trouble. The timing matters — post-1936 emigration is when you see people getting out because they could see what was coming.

Why does my family tree show a gap in the 1930s?

This happens a lot with European families. The mid-to-late 1930s were chaotic — Locarno fell apart, war was clearly coming, and people moved. A lot. Some fled Europe entirely, others relocated within it. When people are constantly on the move, they don’t leave the usual paper trail behind. That’s your gap.

Gavin Crawley is a freelance writer with over 15 years of experience and a strong personal passion for genealogy. He combines his professional writing skills with a deep curiosity about family history, helping others explore their roots through clear, engaging content. Gavin draws on his own research experience to make complex topics more accessible to readers at all stages of their genealogical journey.