One of the earliest – if not the earliest – artworks created by humans are paintings. As early as 15,000 B.C., man was portraying the world around him in cave paintings, such as those in Lascaux.

According to Wikipedia, oil paints were used in England as early as the 13th century for simple decoration. In the High Middle Ages, it is also possible that they were developed for decorative and functional purposes:

Oil painting, as an art form, began to gain steam in the early 15th century. The invention of the art oil painting is often credited to North European painter Jan Van Eyck, who plied his trade during the Renaissance. Van Eyck wanted to mimic nature in his artwork and create highly-detailed paintings that would make his subjects seem alive and life-like. However, the existing painting techniques and oil technologies then weren't suited to his pursuit of realism. Thus, he came to pioneer the art of oil painting, which became popular in his region of North Europe because it worked great in the cold climate there.

In the 16th century, oil painting began to rise in prominence in Venice, one of the centers of the Renaissance. The oil paint proved to be essential for painters who wanted a water-durable medium. Arguably the greatest oil painting was born in Renaissance Italy – Leonardo Da Vinci's Mona Lisa.

Presently, the most common use of oil paint is not in art, but rather domestic. The paint's durable properties and attractive, luminous colors make it a prime choice for both interior and exterior domestic use.