Polish Uhlans (lancers) in parade formation, late-1930s.  The standard Polish lance, which was, as I recall, 2.5 metres in length, is carried.

The lance was, traditionally, a favoured Polish weapon - earlier Polish warriors are said to have carried lances no less that 5 metres long.  It was a difficult weapon to get the best out of, and required detailed training.  These men would also have been expected to master the use of rifles, carbines, machine-guns and hand-held antitank weapons, which they would have used dismounted.  Certainly an élite force, if a bit out of time.  Best regards, JR.

Polish Uhlans on parade.

Adrian helmets, tall boots and horses in the background suggest that they belong to a mounted unit.  

 Heavy machinegun crew

According to my source it’s a Polish Army tank. They had such camouflage during some years between the wars. I place it here because the photograph is in such good focus. I don’t know when the picture was taken. 