Brereton was an ardent Puritan, and at the first signs of approaching war he put himself at the head of the Parliamentary party in Cheshire, calling upon all able-bodied men between the ages of sixteen and sixty to join him at Tarporley, and soon after was appointed by Parliament itself as commander of the Cheshire forces. His career was very nearly cut short at the very beginning of the struggle, for he brought about a riot in Chester by causing the drum to be beaten publicly in the streets for Parliament. He was brought to the Pentice but released, and with difficulty saved from the fury of the citizens, who in later days complained bitterly that the mayor had preserved the life of one who was to be the author of so much disaster to themselves. In Tarporley Church you may see a helmet and breastplate that were dug up in the neighbourhood. They were probably worn by some soldier who fought in one of the earliest battles of the civil war in Cheshire. The first fighting took place in the southern parts of the county. In February, 1642, Brereton was attacked at Tarporley by the king's troops who had marched out from Chester. Entrenchments were thrown up near the church, but the severest fighting was at the neighbouring hamlet of Tiverton, where both sides lost heavily. The Royalist troops retired to Chester and the Parliamentarians to Nantwich, which Brereton made his head-quarters. From these two places the two parties 'contended which should most prevail upon the affections of the county to declare for them and join them'. Brereton's task was the capture of the important city of Chester, in order to prevent assistance reaching the king from Ireland. To this end he placed troops on the principal roads leading to the city. The roads from the south were watched by the Nantwich forces, who captured and occupied Beeston Castle. On the north Warrington Bridge was seized to prevent help coming from Lancashire or from Scotland, which remained loyal to Charles. Norton Priory and the Norman castle of Halton, already in ruins, were fortified and held by the Roundheads. A strong force was posted at Northwich which commanded the main road through the forest of Delamere, thus completing a chain of garrisons along the valley of the Weaver from Nantwich to the Mersey. On the Welsh side the border castles of Holt on the Dee and Hawarden in the county of Flint were attacked and occupied by the Parliamentarians, who thus prevented the arrival of reinforcements from the west.