With the war now consisting of frequent long marches and fewer major engagements, armour became increasingly unpopular amongst the troops, who now routinely abandoned it as cumbersome and uncomfortable. At Christmas 1635 the Swedish chancellor Oxenstierna wrote “AO horsemen’s or soldier’s harness or pots need be sent here, since they have become little used, but mostly cast off because of the long marches one is engaged in here." However, as Montecuccoli writing about 1640
Army arrayed for battle
At least implies that Swedish cavalry (like other demi-cuirassiers) wore armour, it would appear that it came back into use, thus Armoured classification is allowed from 1640.
World History
