The contribution is mainly based on the record and identification of the papers truly used by copyists in Egypt, and in Yemen, along the period, with some glances on Sudan and Ethiopia (Islamic areas). It will focus on papers bearing watermarks, which were imported commodities from Europe. Its aim is to know the Companies which were trading on both sides of the Red Sea, then the countries which were producing and exporting the paper sheets. Starting in the field of technics and the art of the book / codicology, we have collected papers bearing watermarks in different places in Yemen. Some are already documented and published (http://www.anne.regourd.org/docs/Filigrane-Zabid.pdf; « Les routes commerciales entre Zabîd et l’Europe : les papiers filigranés de fonds manuscrits de Zabîd (Yémen, fin 18e-milieu 20e s. »). The overwhelming majority of the extant copies and original manuscripts are from the 17th to the beginning of the 20th Centuries. The following step consisted in taking these watermarks as an original source for the historical study of the Paper Trade in the area. Some researches already available for Egypt and Sudan in the same period made the comparison possible; as for the manuscripts of Ethiopia, I recently made a few, but fruitful investigations. I could eventually evidence the struggle between Italy and Turkey to control the market. Indian paper sheets were also used in Yemen (beginning of the 20th C. at least). Was the West Bank of the Red Sea a place from which the paper sheets were going to some places in Subsaharian Africa, like Nigeria, in competition with other Trade paths? Until the 19th C., traders were conveying cargos, but were not coming back with empty bags. For what commodities were they exchanging paper sheets? Our increasing knowledge of the paper is a tool to date when a manuscript was copied. Moreover, the roots of Trade are aimed at here, which are as well those of the circulation of people and ideas.