Actually, I'm cheating and covering two (almost identical) units - the meat of the French Heavy Cavalry - Cuirassiers (blue jackets above) and Carabiniers (white jackets).
These are the guys that provided the muscle when it was needed. Big men on big horses, kept in reserve until the enemy had been softened up by the artillery and infantry. Then, when the time was right, the massed squadrons of heavy cavalry would be unleashed for the decisive charge that punched a huge hole in the enemy line, and marked the beginning of the end of the battle.
They were effectively the last troops to still wear armor into battle. The use of gunpowder had largely made armor redundant, as bullets could now penetrate the metal, and the additional shattering would make wounds more serious. These heavy cavalry units howeveer still wore a metal breatplate, or
cuirass, from which the cuirassiers took their name.
These were the most expensive men in a Napoleonic army, and given the difficulties the French experienced finding suitable horses in the period soon after the Revolution, very "valuable". These weren't troops you just "threw away on a whim." You had to pick the right moment to inject them into a battle.
Because they were big men on big horses, carrying the additional weight of armor, they were also slower moving than the lighter cavalry units such as chasseurs and hussars. They therefore relied on support of these lighter cavalry types to exploit the success of the charge, by pursuing enemy fleeing from the field, while the heavy brigade came to a halt and reformed their ranks.
In the French army, cuirassier and carabinier regiments comprised four squadrons, each of 120 men (6 figures in my army which is scaled down to one figure represents 20 men).
When preparing to attack, a cavalry regiment would deploy in "column of squadrons". Each squadron would deploy in a line, with the squadrons drawn up one behind the other. The distance between each line was critical, as if the first line became disordered during the course of the charge, there had to be sufficient space between it and the following squadron to prevent those behind from crashing into their own men.
When moving forward initially, a regiment would keep at least 40 yards between each squadron's line, enabling it to wheel to form one long line if faced with an attack from the flank. As the speed of the advance increased, the distance would increase to up to 150 yards, allowing more time to come to a halt if required.
French cuirassiers and carabiniers ignored the element of firepower, charging directly with the sword, relying on their size and weight to inflict the damage. (Supporting artillery and possibly also infantry would provide the fire support for a charge).
If the charge did not go well, those supporting infantry would then be required to provide cover for the retreating horsemen, enabling them to regroup, and perhaps prepare for another attempt, back in "friendly territory".
