It will come as little surprise that the modern spa was first developed by Jacuzzi. Just like Scotch Tape, Kleenex, Band-aid and Rollerblade, it’s a brand name word that became the generic word for the item itself.

Like many such genericized words, Jacuzzi is the go-to word for hot tub or spa because the brand both created and then dominated its category.

But while the concept of bathing in hot water certainly didn’t begin with Jacuzzi hot tubs, it was the seven Jacuzzi brothers who revolutionized the hot tub industry.

According to Jacuzzi family lore, in 1956, a baby family member developed rheumatic fever, leaving him with juvenile rheumatoid arthritis; he was treated with monthly hydrotherapy treatments at the hospital.

Because the treatments alleviated his pain, the family responded by inventing a hydrotherapy pump so that he could get regular hot water therapy at home.

The portable pump could be dropped into any normal sized bathtub. Called J-300, it could convert a bath tub into a rejuvenating hydro-therapeutic spa and the family marketed their innovative product to hospitals and schools.

Then in 1968, Roy Jacuzzi, a thirdgeneration family member, invented the first whirlpool bath.

By incorporating body jets into the sides of the tub, it became the bath that almost single-handedly created an industry. By the 70’s, larger units were being manufactured with built-in heating features and filtration systems.

It was this that caused the name Jacuzzi to be forever imprinted on everyone’s mind as a synonym for the spa.

But while the world owes a debt of gratitude to the Jacuzzi family, humans have always sought the embracing warmth of water. In fact, the history of hot tubs and spas is nearly as long as the history of mankind.

Even before hot tubs and spas were fabricated, people enjoyed the relaxation benefits of natural hot springs.

The earliest hot tubs were called calderas and they were heated with hot stones. Ancient Egyptians are believed to have enjoyed these baths as early as 2000 B.C. Perhaps the first fabricated hot tub was chiseled out of granite for King Phraortes of ancient Persia in 600 B.C.

The earliest known spa that is still in existence is in Merano, Italy, where there is evidence that it was used 5,000 years ago.

In Greek and Roman times, it was common to build baths around natural hot springs and volcanoes. The famous Greek physician, Hippocrates, is known to have celebrated the therapeutic properties of heated water; other Greek philosophers including Plato wrote of the benefits of hydrotherapy.

Most historians attribute the word “spa” to originate from either of the Latin phrases “Sanus per Aquam” or “Sanitas per Aquas” both of which translate to “health through water.” Some believe the word originates from the name of the Belgian City, Spa, famous for its natural hot springs, but it is likely the other way around, and the city was named for its many healthy waters.

“Health through water” lost popularity with the decline of the Roman Empire in 476 AD. Admonitions from the prevailing Christian culture discouraged public bathing as a kind of hedonism. Spa bathing was largely abandoned until the 1800’s, when it was mostly the upper classes that enjoyed the luxury.

Meanwhile, in Japan, hydrotherapy had long been a part of the culture. Asian culture, from China to Japan, has revered hot water’s healing power for centuries. The Japanese have a saying, Mizu-no-Kokoro, which translates to “mind like water,” referring to a state of peace and harmony.

Japan’s first onsen (public bathing facility built around a hot spring) opened in 737 A.D. near Izumo Shimane. Centuries later, in 1600, a traditional Japanese inn called a ryokan became popular, featuring communal baths and very large deep bath tubs called ofuro, likely the predecessor to western hot tubs. These early hot tubs were made by cutting wooden wine casks in half and could comfortably hold about four people.

During World War II, western soldiers became acquainted with the Japanese practice of communal bathing in heated waters. It was then that the more modern hot tub began to emerge in the United States, when occupation forces in Japan brought knowledge of ofuros home.

These first U.S. hot tubs, made from used oak barrels, wine tanks and olive vats began appearing in the 1940’s, mostly in California.

And when the Jacuzzi family added the jets, an industry was born.