Since the invention of the fishing rod in the 18th century, fishermen have been using a variety of materials to make fishing line. Before nylon and other modern synthetics were invented, anglers used natural fibers like horsehair, silk, and cotton.
Horsehair was one of the most widely used materials for fishing line in the past. It was strong and had excellent knot retention, making it ideal for tying knots securely. It also had a great stretch and could absorb shock from fish strikes better than other materials at the time.
The downside was that it was expensive and not particularly abrasion-resistant.
Silk was also popular for making fishing line. It was strong and flexible, but also expensive. However, it had superior knot strength compared to horsehair as well as excellent abrasion resistance. In addition to being used as fishing line, silk was also used to tie flies when angling with artificial bait.
Cotton was another material commonly used in past centuries for making fishing lines. It was inexpensive but not very strong or durable compared to horsehair or silk.
It did not have good knot strength either and quickly became soiled if left out in the sun for too long.
In the past, fishermen relied on natural materials such as horsehair, silk and cotton when crafting their own fishing lines. Horsehair provided strength and knot retention while silk offered superior abrasion resistance and knot strength compared to other materials available at the time. Cotton may have been an inexpensive option but lacked strength when compared to other materials.