Paper was a Chinese invention that reached Europe, via the Muslim world, in the twelfth century. By the fifteenth century it was much the most common writing material in Europe, and its production increased rapidly with the development of the printing industry. Paper Online provides a brief history of paper.
Almost all white paper used in the British Isles was imported until the early eighteenth century. Most paper used in Britain came from France, especially Normandy, and the Low Countries. High quality paper, which was often used for writing in manuscript, also came from further afield.
There is a very considerable amount of material about paper online, for which see the links to the right. The classic work on paper and its history remains, Dard Hunter, Papermaking, Second edition (London, 1947), although a more recent volume is Bo Rudin, Making Paper: A Look into the History of an Ancient Craft (Vällingby, Sweden, 1990). An account of paper in Britain is D. C. Coleman, The British Paper Industry 1495-1860: A Study in Industrial Growth (Oxford, 1958).
All paper was made by hand until the early nineteenth century, and before the 1750's all European paper was what is termed "laid" paper. There are specific characteristics of this type of paper that make it useful for purposes of identification. In particular, almost all paper had a watermark; by identifying a watermark it is possible to approximate the date and place of the paper's manufacture. The usefulness of paper and watermarks as bibliographical evidence is especially in identifying who was using a particular stock of paper.