Many months were to pass away before Cromwell was to measure swords with Rupert. He remained under Essex almost to the end of the year, and was present at Turnham Green, when Essex saw Charles, after taking up a position at Brentford in the hope of forcing a passage to London, march off to Reading and Oxford without attempting to strike a blow. Towards the end of 1642, or in the early part of 1643, Cromwell had work found for him which was eventually to breathe a new spirit into the Parliamentary army. Enormous as was the advantage which the devotion of London conferred upon Parliament, London by no means exercised that supreme influence which was exercised by Paris in the times of the French Revolution. Both parties, therefore, put forth their efforts in organising local forces, but of all the local organisations which were brought into existence, the only one entirely successful was the Eastern Association, comprising Essex, Suffolk, Norfolk, Cambridge and Herts, and that mainly because Cromwell was at hand to keep it up to the mark. There was to be a general fund at the service of the association, whilst the forces raised in the several shires of which it was composed were to be at the disposal of a common committee. In England generally the first half of 1643 was a time of desultory fighting, alternating with efforts to make peace without the conditions which might have brought peace within sight. It was not to be expected either that Parliament would accept Charles on his own terms, or that Charles would bow down to any terms which Parliament was likely to offer. Cromwell, at least, took no part in these futile negotiations, and did all that in him lay to clear the counties of the Eastern Association from Royalists, and to put them in a state of defence against Royalist incursions. At some time later than January 23, and before the end of February, he was promoted to a colonelcy. In March he was fortifying Cambridge, and urgently pleading for contributions to enable him to complete the work. Again we find him sending to arrest a Royalist sheriff who attempted to collect soldiers at St. Alban's, and then hurrying to Lowestoft to crush a Royalist movement in the town. After this no more is heard of Royalism holding up its head in any corner of the association, and to the end of the war no Royalist in arms again set foot within it. By the end of May it was joined by Huntingdonshire, the county of Cromwell's birth.