Hi RAmC, nice one. Your posting has got me thinking about these early actions again (I'm curently "stuck" in 1809 to 1811...
Anyone interested in the Peninsular might find it useful to have a look on the following website,
http://www.napoleon-series.org. João Centeno has copied onto the web site some excellent maps of the major engagements of the Peninsular War and come of the campaigns. The maps are from História da Guerra Civil e do Estabelecimento do Governo Parlamentar em Portugal: Comprehendendo a história diplomatica, militar e política d'este reino desde 1777 até 1834
They are all in colour, and are unique as they provide a Portuguese perspective of the battles and campaigns. All forces, Anglo-Portuguese and French are shown. The detail of place names and topography are excellent – see under the what’s new section and look for Centeno.
I don’t have all my sources to hand, and I have had a little difficulty establishing the full extent of French forces engaged in the three or four separate combats in this initial phase of the Peninsular War....
Certainly, most sources agree that the French are limited to around 4,500 troops of all arms. But there’s is some doubt as to the contribution of the 4th leger - the units engaged are from from both Delaborde and Loison. The very small combat that took place between Anglo and French pickets north of Obidos can be discounted. The French’s first position was indeed on low rising ground near the settlement of Roliça. Wellesley was advancing from the North and had sent Ferguson’s strong detachment off to the east, his left, and the Portuguese troops to the west (right) in two outflanking marches.
There is a road to the east of Roliça towards Bombarral which makes its way somewhat to the (Allied) left of Delaborde’s second position behind the settlement of Columbeira. Wellesley had detached Ferguson with two and half brigades, six guns and some cavalry, to both outflank Delaborde and to guard against a possible French move on the British flank. Delaborde, when retreating from Obidos, had also made some small detachments to Bombarral and Cadaval in the hope of making contact with these expected French reinforcements (approaching from the direction of Abrantes). There is also an account of him detaching (at least some of) the Swiss to Peniche
Upon seeing the outflanking marches, Delaborde skilfully retires behind his screen of light cavalry and infantry screen to his second position away from the advance of Wellesley’s remaining British brigades. As you point out, this position is naturally very strong. According to some accounts the French had cleared their initial position and Wellesley deployed his brigades into battle line. British skirmishers exchanged fire with the retiring French – who were also in reach of and came under fire from the British artillery. Other accounts report at least three separate British assaults before the French are forced to give way in the face of superior numbers. Certainly, we know of the attacks of Nightingale’s brigade – Hill ordered a general advance of the British line and the heights were eventually gained (on the western side). The French had put up a fairly stubborn resistance but had to retire once the heights were gained. Delaborde withdrew losing some of his artillery - the final stages of the action taking place near to Azambugeira.
The ground immediately to the north of Roliça is undulating but suitable for cavalry. The ground between Roliça and the heights above Columbeira is more broken, but (obviously) still passable by formed cavalry (albeit in small numbers) until the height themselves are reached. Apart from the rough ground in the defiles, the heights themselves can also be reached by a very steep road to the British right and French left. Once reached, the ground beyond the heights is more open but undulating.
There’s a useful description of the combat and a photo of the heights in Robertson, “Wellington at war in the Peninsular”, pp 31-39, some useful directions for finding the sites in Paget’s “Wellington’s Peninsular War” pp 61-66 and two first hand accounts of the battle itself in on pp13-14 of Fletcher, “Voices from the peninsular: eyewitness accounts by soldiers of Wellington’s Army 1808-1814”. Windrow and Embleton have a plate of a battalion company private 29th and drummer of the 50th.
Best wishes
Sprunglin