About a year ago Gregory Hanlon, a professor at Dalhousie University in Halifax NS, published a book on the 1636 Battle of Tornavento. Italy 1636, Cemetery of Armies provides an excellent history on both the campaign in northern Italy and its culminating battle. Hanlon also looks at the issues of the morale and motivation of soldiers in combat, combat lethality and mortality rates, and the effect of war on civilians.
His examination of tactics, however, is what may be of the greatest interest to readers of this message board. Hanlon is constrained by the paucity of original sources on the battle. Thus Hanlon is forced to extrapolate some tactical deployments in light of details outlined by other modern authors. For the Spanish army Hanlon depends heavily on the research done by Peter Engisser and Pavel Hrnčiřík, Nördlingen 1634, Die Schlacht bei Nördlingen – des Wendepunkt des Dreißigjährigen Krieges, (2009). Unfortunately, Hanlon's explanation of the frontages of the Spanish infantry esquadrons neglects to apply the details provided by Engisser and Hrnčiřík.
French tactical deployments are also briefly addressed, drawing on the work of David Parrot, Richelieu's Army, Government and Society in France 1624-1642, (2001).
Hanlon also cites a number of Seventeenth Century Italian and French sources. It is from one of these, Galeazzo Gualdo Priorato, Il maneggio delle armi (1642), that the following description of infantry skirmishing is based on:
"At Tornavento the Spanish advance stopped along the plateau's edge or a few metres below the Panperduto canal, but the fighting continued as a scaramuccia [skirmish]. This particular tactic does not figure often in the drillbooks, but Gualdo Priorato provides a description of it, adding that it was ‘di grande osservanza'. The musketeers alternated between reloading and moving up to the firing line. Soldiers in combat accelerated the reloading process to half a dozen sequences. Standing in the rear, fight foot immobile, holding the loaded weapon at an oblique angle (so as to not shoot a comrade by accident), the musketeer paced forward carefully behind the man in front, and then reached the front row spread out as much as he was able, and once being certain that no friendly marksman was standing in front, placed his musket on its support, aimed deliberately at an enemy soldier and took his time to fire. Then he retraced his steps to the rear without turning his back to the enemy, while another man stepped forward to take his place. This form of musketry was not executed to specific orders and each man returned to the firing line as quickly as he had reloaded – in theory. ‘The more this is done individually (sconcertatamente) the more likely it succeeds because there is no confusion or congestion'. (Priorato) It was confusion, stressed the author-soldier, that was the mother of all disasters. Firing in this manner could continue all day." (Hanlon, pp. 129-130)
Hanlon also offers some details on cavalry charges:
"Early in the Thirty Years' War it was common for two bodies of cavalry to stop and exchange fire at about 30 metres' distance, before on side approached to mix with their adversary. Cavalry engagements were brief, frantic actions where horsemen advanced without breaking into a gallop into each other's ranks from opposing directions. There was no ‘shock' of horses and riders, if indeed the two bodies came into reach at all: rather cavaliers tried to push their way into gaps in the enemy array and to break open their formation. The more ‘porous' formation would quickly be dominated and seek to disperse and reform. In the tight spaces men fired pistols at their adversaries at close range, drew their sabres, and then slashed any opponent within reach, if they were able to retain their sang-froid to control their exited mount and to use their weapons effectively. Only a few minutes would elapse before buglers sounded the order to disengage and reform. Then a second line repeated the forces until one of the formations decided to withdraw." (Hanlon, p. 108)
For further inquiry here is Hanlon's citation for this description:
Gavin Robinson, "Equine Battering rams? A Reassessment of Cavalry Charges in the English Civil War", Journal of Military History, 75 (2011), pp. 719-731; see also Frédéric Chauviré, "Le problème de l'allure dans les charges de cavalerie du XVIe auXVIIe siècle", Revue Historique des Armées, 249 (2007), pp. 16-27; the same author's recent book, Histoire de la cavalrie, constitutes the best introduction to date, pp. 278-293; see also Jean Michel Sallmann, "Le chevel, la pique et le canon: Le role tactique de la cavalerie du XVIe au XVIIe siècle", in Daniel Roche and Daniel Reytier (eds), Le chevel et la guerre du XVIe au XVIIe siècle, (Paris, 2002), pp. 253-267.
The two points detailed above are what I primarily gleaned from the book in terms of tactics of the period. The book is of course also an excellent study of a neglected part of the history of the Thirty Years War outside of Germany.