History of saunas...

Etymology

The word sauna is an ancient Finnish word referring to the traditional Finnish bath as well as to the bathhouse itself. The proto-Finnic reconstruction is *savna. There are etymological equivalents in the Baltic-Finnic languages such as the Ingrian and Votic word sauna, Estonian saun and Livonian sona. The word suovdnji in Sámi means a pit dug out of the snow, such as a hole for a willow grouse. In Baltic-Finnish, sauna does not necessarily mean a building or space built for bathing. It can also mean a small cabin or cottage like a cabin for a fisherman.

First saunas

The oldest known saunas were pits dug in a slope in the ground and primarily used as dwellings in winter. The sauna featured a fireplace where stones were heated to a high temperature. Water was thrown over the hot stones to produce steam and to give a sensation of increased heat. This would raise the apparent temperature so high that people could take off their clothes.

Evolution

Eventually the sauna evolved to use a metal woodstove, or kiuas, with a chimney. Air temperatures averaged around 70-80 degrees Celsius (160-180 degrees Fahrenheit) but sometimes exceeded 90 °C (200 °F) in a traditional Finnish sauna. Steam vapor, also called löyly , was created by splashing water on the heated rocks.

The steam and high heat caused bathers to perspire. The Finns also used a vihta (Western dialect, or vasta in Eastern dialect), which is a bundle of birch twigs with fresh leaves, to gently slap the skin and create further stimulation of the pores and cells.

The Finns also used the sauna as a place to cleanse the mind, rejuvenate and refresh the spirit, and prepare the dead for burial. The sauna was (and still is) an important part of daily life, and families bathed together in the home sauna. Indeed, the sauna was originally meant to be a place of mystical nature where gender/sex differences did not exist. Because the sauna was often the cleanest structure and had water readily available, Finnish women also gave birth in the sauna.

Although culture of sauna nowadays is more or less related to Finnish culture, it's important to note that the evolution of sauna have happened around the same time both in Finland and the Baltic countries sharing the same meaning and importance of sauna in daily life. The same sauna culture is shared in both places still to this day.

When the Finns migrated to other areas of the globe they brought their sauna designs and traditions with them, introducing other cultures to the enjoyment and health benefits of sauna. This led to further evolution of the sauna, including the electric sauna stove, which was introduced in the 1950s and far infrared saunas, which have become popular in the last several decades.