Typically the medieval armies both on the march and in battle array were organised in three ‘battles’. Apart from Barrett’s bizarre interpretation with the English arrayed on the north and the Scots to the south, there are two alternative deployments given by modern authors.
English Heritage, following Oman, show a deployment in a single body with just a small reserve protecting the horses, the majority of the baggage apparently have been left in Thirsk. The alternative deployment is shown by Bradbury. He depicts a deployment in three lines, with archers who were protected by dismounted men at arms in the first line, a main battle with the senior figures and the knights centred on the Standard, and a small cavalry reserve which also guarded the horses. Smurthwaite adds a separate line behind the standard and on the flanks comprising local levies and shows the reserve at a considerable distance to the rear.
The English Heritage report shows a battalia some 550 metres wide. However, given the nature of the terrain, as so far reconstructed, it seems likely that the English would have attempted to deploy across the Great North Road, with the marsh of Cinnamire protecting their left flank, and perhaps with the slight valley between the modern Brompton Grange and The Grange, which might perhaps prove to have been another small marshy area, on their right flank. This would give a frontage of up to 1000 metres with Standard Leeze at its centre. However this may be considered too wide for a 12th century deployment with the numbers likely to have been present.
The Scottish army was deployed in four battles according to most modern accounts. However they vary between Bradbury’s depiction of them aligned one behind the other to Oman’s plan, followed by English Heritage, where they are deployed in a diamond formation. The latter has been followed here. All are agreed that David with his reserve was at the rear. Prince Henry was on the right with one infantry wing and a small body of mounted knights, the Lothian troops on the left wing and the Galwegians in the centre.
Initially David’s battle plan had been to see his best armed and his armoured men take the fight to the English. But there was no love lost between the native Galwegian troops and these knights and their supporters from the increasingly feudalised lowland areas. Unfortunately, to maintain the support of the wayward Galwegian infantry he had to give them the honour of leading the attack, even though they had no protection from the English arrows and were no match for the well equipped English men at arms. In this lay the seeds of David’s dramatic defeat.