String instruments, such as the lute and the lyre, came from Asia in ancient times.
Then the bow came to Europe from Persia. In the Middle Ages, musicians in Europe played a number of string instruments with the bow, including one called the rebec, which had two or three strings.
In the 15th century, a six-stringed instrument called the viol became popular. There were three kinds of viols, one for each of the three voice parts: treble, tenor, and bass.
But the viol had a weak tone, so instrument makers gradually changed its form until the violin family emerged around 1600. The treble viol became the violin, the tenor viol became the viola, and the bass viol became the cello.