Yet once more Henry's stay on the English side of the Channel was but for a year. In 1158 he again departed to plunge into schemes of continental conquest. This time it was an attempt to annex the great county of Toulouse, and so to carry the borders of Aquitaine to the Mediterranean, which distracted him. Naturally Louis of France was unwilling to see his great vassal striding all across his realm, and did what he could to hinder him. Into the endless skirmishes and negotiations which followed the raising of the question of Toulouse it would be fruitless to enter. Henry did not achieve his purpose, indeed he seems to have failed to use his strength to its best advantage, and allowed himself to be bought off by a futile marriage treaty by which his eldest son was to marry the French king's daughter (1160). This was to be but the first of many disappointments in this direction; there was apparently some fatal scruple, both in Henry's own mind and in that of his continental subjects, as to pressing their suzerain too hard. But it must also be remembered that a feudal army was an inefficient weapon for long wars, and that the mercenaries, by whom alone it could be replaced, were both expensive and untrustworthy. Henry developed as far as he was able the system of "scutage" (q.v.) which his grandfather had apparently invented; by this the vassal compounded for his forty days' personal service by paying money, with which the king could hire professional soldiers. But even with this help he could never keep a large enough army together. Quarrel with the church. Becket.