The history of watercolour is inextricably bound to the history of paper, invented in its present form by the Chinese shortly after 100 AD. Papermaking was introduced to Spain by the conquering Moors in the mid-12th century and spread to Italy 25 years later. One of the earliest paper centers was Fabriano, Italy with mills in operation by 1276.
The forerunner of watercolour painting was buon fresco painting: wall-painting using watercolour paints on wet plaster. The most famous example of buon fresco is, of course, the Sistine Chapel, begun in 1508 and completed in 1514. In Europe, as early as the 15th century, Albrecht Durer (1471-1528) was painting in watercolour. Durer's influence was partly responsible for the first school of watercolour painting in Europe, led by Hans Bol (1534-1593).
Great interest in watercolour was created by the reporter/artists of the American Civil War. Their on-the-scene drawings of the battlefields were used as illustrations in the newspapers and magazines of the day, the most famous being Harper's Weekly.