The Conqueror in a measure, and Henry I. with more clearness, perceived this, and foresaw the result. They were careful not only to call themselves English kings, but nominally at least to maintain English customs, and to rule by English laws. One by one the great houses which furnished rivals to their power dropped before them, and Henry I. at the close of his reign was so strong that, had it not been for the fact that he had by habit and routine made himself a law to himself, he might easily have played the part of a tyrant. But the forces which he and his father had so sturdily repressed were not extinguished; nor was the administrative system, by which they at once maintained the rights of the English and kept their own grasp of power, sufficiently consolidated to stand steadily when the hands that had reared it were taken away. [Sidenote: Question of succession. ] This also, it may seem probable, Henry I. distinctly saw. It was to his apprehensions on this account that for years before his death he was busily employed in securing the succession by every possible means to his own children. The feeling which led him to do so is not quite capable of simple analysis. He had no great love for his daughter, the empress Matilda; what paternal affection he had to lavish had been spent on his son William, whose death was no doubt the trouble that went nearest to his heart. We cannot suppose that he cared much for the people whom, although they had delivered him more than once in the most trying times, he never scrupled, when it suited his purpose, to treat as slaves. It would almost seem as if he felt that, unless he could anticipate the continuance of power in the hands of his daughter and her offspring, his own tenure of it for the present would be incomplete, and the great glory of the sons of Rollo would suffer diminution in his hands. [Sidenote: Precautions taken by Henry I. ]