Hi Richard – short answer: For Napoleonics you pay for a battalion, as in BP the basic infantry ‘unit’ on the table represents a battalion.
Long Answer!
Regiments and battalions can be confusing and sometimes we use the term interchangeably which can lead to further confusion. Typically a Regiment was an army organisational unit that contained one or more Battalions which operated on the battlefield. The exact way a Regiment was organised varied by army, and also evolved over time, and could also vary between different regiments in the same army.
For example, the British forces sent overseas to fight in the Napoleonic period typically sent a single battalion from a regiment. (This leads to using the term regiment and battalion interchangeably.) However the French often had 3, 4 or even 5 battalions from a regiment all serving together. Things get confused though as a French regiment could have a battalion serving in Spain and another battalion serving in Russia. This can cause lots of confusion when references only refer to a Regiment (e.g. how were they in different places at the same time?!).
As wargamers, most of the time (!), the regiment of a unit should help us understand all of the those exciting uniform details, like cuff colours. Battalions are then the actual units used on the field/table.
Hope this helps?
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