Edward's wife, Queen Philippa, was a native of a French province adjoining Flanders, which was also engaged in the production of cloth. (See map facing p. 128.) She used her influence in behalf of the establishment of woolen factories at Norwich, and other towns in the east of England, in 1336. Skilled Flemish workmen were induced to come over, and by their help England successfully laid the foundation of one of her greatest and most lucrative industries. From that time wool was considered a chief source of the national wealth. Later, that the fact might be kept constantly in mind, a square crimson bag filled with it--the "Woolsack"--became, and still continues to be, the seat of the Lord Chancellor in the House of Lords. 237. The Beginning of the Hundred Years' War, 1338. Indirectly, this trade between England and Flanders helped to bring on a war of such duration that it received the name of the Hundred Years' War. Flanders was at that time a dependency of France (see map facing p. 128), but its great commercial towns were rapidly rising in power, and were restive and rebellious under the exactions and extortion of their feudal master, Count Louis. Their business interests bound them strongly to England; and they were anxious to form an alliance with Edward against Philip VI of France, who was determined to bring the Flemish cities into absolute subjection. Philip was by no means unwilling to begin hostilities with England. He had long looked with a greedy eye on the tract of country south of the Loire,[2] which remained in possession of the English kings, and only wanted a pretext for annexing. Through his alliance with Scotland, he threatened to attack Edward's kingdom on the north. Again, Philip's war vessels had been seizing English ships laden with wool, so that intercourse with Flanders was maintained with difficulty and peril. [2] Names Aquitaine (with the exception of Poitou). At a later period the province got the name of Guienne, which was a part of it. (See map facing p. 128.) Edward remonstrated in vain against these outrages. At length, having concluded an alliance with Ghent, the chief Flemish city, he boldly claimed the crown of France as his lawful right,[1] and followed the demand with a declaration of war. Edward based his claim on the fact that through his mother Isabelle he was nephew to the late French King, Charles IV, whereas the reigning monarch was only cousin of that monarch. To this the French replied that since their law excluded women from the throne, Edward's claim was worthless, because he could not inherit the crown of France from one who could not herself have worn it. [1] Claim of Edward III to the French Crown