The year 1138, which began with the siege of Bedford castle, has to be reckoned as belonging to the time when Stephen's power was still to all appearance unshaken. But it is the beginning of the long period of continuous civil warfare which ended only a few months before his death. Judgment had already been passed upon him as a king. It is clear that certain opinions about him, of the utmost importance as bearing on the future, had by this time fixed themselves in the minds of those most interested - that severe punishment for rebellion was not to be feared from him; that he was not able to carry through his will against strong opposition, or to force obedience; and that lavish grants of money and lands were to be extorted from him as a condition of support. The attractive qualities of Stephen's personality were not obscured by his faults or overlooked in passing this judgment upon him, for chroniclers unfavourable to him show the influence of them in recording their opinion of his weakness; but the general verdict is plainly that which was stated by the Saxon Chronicle under the year 1137, in saying that "he was a mild man, and soft, and good, and did no justice." Such traits of character in the sovereign created conditions which the feudal barons of any land would be quick to use to their own advantage.

The period which follows must not be looked upon as merely the strife between two parties for the possession of the crown. It was so to the candidates themselves; it was so to the most faithful of their supporters. But to a large number of the barons most favourably situated, or of those who were most unprincipled in pursuit of their own gain, it was a time when almost anything they saw fit to demand might be won from one side or the other, or from both alternately by well-timed treason. It was the time in the history of England when the continental feudal principality most nearly came into existence, - the only time after the Conquest when several great dominions within the state, firmly united round a local chief, obtained a virtual, or even it may be a formal, independence of the sovereign's control. These facts are quite as characteristic of the age as the struggle for the crown, and they account for the continuance of the conflict more than does the natural balance of the parties. No triumph for either side was possible, and the war ended only when the two parties agreed to unite and to make common cause against those who in reality belonged to neither of them.

From the siege of Bedford castle, Stephen had been called to march to the north by the Scottish invasion, which early in January followed the failure of David's embassy. All Scottish armies were mixed bodies, but those of this period were so not merely because the population of Scotland was mixed, but because of the presence of foreign soldiers and English exiles, and many of them were practically impossible to control. Portions of Northumberland down to the Tyne were ravaged with the usual barbarities of Scottish warfare before the arrival of Stephen. On his coming David fell back across the border, and Stephen made reprisals on a small district of southern Scotland. But his army would not support him in a vigorous pushing of the campaign. The barons did not want to fight in Lent, it seemed. Evidences of more open treason appear also to have been discovered, and Stephen, angry but helpless, was obliged to abandon further operations.

Shortly after Easter David began a new invasion, and at about the same time rebellion broke out in the south-west of England, in a way that makes the suspicion natural that the two events were parts of a concerted movement in favour of Matilda. This second Scottish invasion was hardly more than a border foray, though it penetrated further into the country than the first, and laid waste parts of Durham and Yorkshire. Lack of discipline in the Scottish army prevented any wider success. The movement in the south-west, however, proved more serious, and from it may be dated the beginning of continuous civil war. Geoffrey Talbot, who had accepted Stephen two years before, revolted and held Hereford castle against him. From Gloucester, where he was well received, the king advanced against Hereford about the middle of May, and took the castle after a month's blockade, letting the garrison off without punishment, Talbot himself having escaped the siege. But by the time this success had been gained, or soon after, the rebellion had spread much wider.