Saunas spread from Finland to the rest of the world through Finnish emigration to North America in the late 1800s, the visibility of Finnish athletes at the Olympics in the 1920s through 1950s, the rise of prefabricated sauna kits after World War II, and landmark scientific research that validated the health benefits.
You'd be forgiven for thinking the sauna is a modern wellness trend. Walk into any gym, spa, or recovery center and you'll see infrared panels, cedar benches, and people sweating in silence. But the sauna's journey—from a hole in the ground in northern Finland to a global health tool—is a story of migration, war, and Olympic athletes.
Here's how it happened.
The Finnish Original: 2000 BCE to 1800s
The first saunas weren't heated by electric stoves. They were dug into hillsides or built from logs, heated by a pile of stones fired red-hot, then doused with water. The savusauna (smoke sauna) had no chimney. You let the smoke fill the room, then aired it out before entering. The soot on the walls was a feature, not a bug—it acted as a natural disinfectant.
For Finns, the sauna wasn't recreation. It was where babies were born, where the sick were treated, where the dead were washed before burial. It was the only heated space in a frozen country. By the 1800s, there was roughly one sauna for every five Finnish households.
But Finland was a remote, sparsely populated part of the Russian Empire. The rest of the world had no idea this practice existed.
The Breakthrough: Finnish Emigration to North America (Late 1800s)
The first mass export of sauna culture happened through human movement. Between 1870 and 1920, roughly 300,000 Finns left for the United States and Canada. They settled in the Upper Midwest—Minnesota, Michigan, Wisconsin—and in northern Ontario.
They didn't leave their saunas behind.
Finnish immigrants built smoke saunas and later wood-burning saunas in their new homes. Non-Finnish neighbors saw them. Some tried them. The term "Finnish bath" entered English-language newspapers by the 1880s. A reporter for the New York Times described one in 1891 as "a curious custom of the Finns in which they heat themselves to the point of perspiration and then beat themselves with birch branches."
It was written off as eccentric. But the seed was planted.
The Olympic Connection: 1920s–1950s
The second wave came through sport.
Finnish athletes dominated distance running in the early 20th century. Paavo Nurmi won nine Olympic gold medals between 1920 and 1928. Finnish wrestlers, skiers, and runners traveled to competitions around the world. They brought their sauna habits with them.
At the 1936 Berlin Olympics, the Finnish team installed a mobile sauna. Other athletes noticed that Finnish competitors seemed to recover faster between events. Coaches from Sweden, Germany, and the United States started asking questions.
By the 1950s, the International Olympic Committee had seen enough. The Finnish team brought a sauna to the 1952 Helsinki Olympics, and the facility was used by athletes from multiple countries. The sauna had moved from a cultural curiosity to a performance tool.
The Post-War Boom: 1950s–1970s
World War II scattered Finnish soldiers and refugees across Europe. Many had grown up with saunas. After the war, they built them wherever they settled.
But the real accelerator was the rise of prefabricated sauna kits. In the 1950s, Finnish companies like Harvia and Tylö started manufacturing electric sauna heaters and modular sauna rooms. For the first time, you didn't need to be a Finnish immigrant or a log cabin builder to own a sauna.
The kits were sold to hotels, gyms, and wealthy homeowners in Germany, the United Kingdom, and Japan. By the 1960s, saunas were appearing in American health clubs. The New York Times ran a 1964 piece titled "The Sauna Comes to America," noting that "the Finnish bath is no longer a novelty but a fixture in the modern home."
The Science Validates the Tradition: 1980s–Present
The cultural spread was one thing. The scientific spread was another.
In the 1980s and 1990s, researchers in Finland and Japan began studying the physiological effects of heat exposure. They found that sauna use improved cardiovascular function, reduced inflammation, and stimulated heat shock proteins—the cellular repair mechanisms that protect against protein misfolding and oxidative stress.
The landmark study that changed the conversation came in 2015. Researchers at the University of Eastern Finland published a 20-year follow-up of 2,300 middle-aged men. They found that men who used a sauna 4 to 7 times per week had a 40% lower risk of dying from cardiovascular disease compared to men who used it once a week. The relationship was dose-dependent. More sessions, better outcomes.
That study was covered by the BBC, CNN, and The New York Times. Suddenly, the sauna wasn't just a Finnish tradition or a luxury spa amenity. It was a tool for longevity.
Where the Sauna Is Today
You can now find saunas in nearly every country in the world. South Korea has jjimjilbangs—public bathhouses with sauna rooms that are a cultural institution in their own right. Germany has Saunakultur, with over 2,000 public saunas. Russia has its banya. The United States has saunas in gyms, hotels, and an increasing number of private homes.
The modern twist? Infrared saunas, which heat the body directly rather than the air, have made the practice accessible to people who can't tolerate the 80–100°C temperatures of a traditional Finnish sauna. Portable sauna tents and blankets have dropped the entry barrier even lower.
But the core principle is unchanged: controlled heat exposure, followed by cooling, repeated intentionally.
What This Means for You
The sauna's spread wasn't driven by marketing. It was driven by results. Finns used it because it worked for survival. Athletes adopted it because it worked for recovery. Scientists validated it because the data held up.
If you're curious about starting, the research supports starting slow:
- Two to three sessions per week
- 10 to 15 minutes each
- A temperature that feels warm but not punishing
Finnish men who sauna daily have the best outcomes, but the benefits appear at lower frequencies too.
And if someone asks why you're sitting in a hot room for no apparent reason, you can tell them: this started in a country where winter lasts six months, and it took 2,000 years for the rest of the world to figure out they were onto something.
Frequently asked questions
How did saunas first spread outside Finland?
The first major export of sauna culture came through Finnish emigration. Between 1870 and 1920, roughly 300,000 Finns moved to the United States and Canada, settling in the Upper Midwest and northern Ontario. They built saunas in their new communities, and non-Finnish neighbors began to take notice.
What role did the Olympics play in popularizing saunas?
Finnish athletes who dominated international sport in the early 20th century brought their sauna habits to competitions around the world. At the 1936 Berlin Olympics, the Finnish team installed a mobile sauna, and other athletes noticed their faster recovery between events. By the 1952 Helsinki Olympics, athletes from multiple countries were using the Finnish sauna facility.
What does the research say about how often you should use a sauna?
A 20-year study of 2,300 middle-aged men published in 2015 by researchers at the University of Eastern Finland found that men who used a sauna 4 to 7 times per week had a 40% lower risk of dying from cardiovascular disease compared to men who used it once a week. The article notes that benefits appear at lower frequencies too, and suggests starting with two to three sessions per week of 10 to 15 minutes each.
What is an infrared sauna and how is it different from a traditional Finnish sauna?
Infrared saunas heat the body directly rather than heating the surrounding air. This makes them accessible to people who find the 80 to 100 degrees Celsius temperatures of a traditional Finnish sauna difficult to tolerate. Portable sauna tents and blankets have further lowered the barrier to entry for people who want to try heat exposure.