Taken by me at the Warsaw Army Museum back in 2006.
There were loads of uniforms relating to the Soviet-Polish war: unusually for the Poles most of them being infantrymen, which was a nice change. I have no interest in dress uniforms, so those have been omitted.
The intervening glass, awkward positions and what was even then a cheap camera reduce the picture quality. I would appreciate links to better quality versions.
The 1919-1920 uniforms in Warsaw a 3.3 MB .zip file if you want to download all of them.
W20: a cabinet for the Poznan army and the Silesian Uprising, 1919.
W21: insurgent from the time of the 3rd Silesian Uprising.
W22: the uniform of General Dowbor-Musnicki.
W23: officer of a ballon unit.
W24: corporal of the 1st Wielkopolski (Great Poland) Lancer Regiment.
W25: a cabinet labelled Russo-Polish War.
W26: a private of the 3rd Infantry regiment, with German model tunic and Springfield rifle.
W27: a trooper of the 1st Krechowiecki Lancer Regiment.
W28: uniform of General Szeptycki.
W29: a cabinet labelled Battle of Warsaw. Note the lance with pennon in the background. Rifles were a Wernd and a Berthier.
W30: a uniform for a Haller unit in "horizon blue" and Adrian helmet.
W31: a trooper of the 14th Jazlowiecki Lancer Regiment.
W32: a flying officer of the Air Force.
W33: Captain of the 2nd Lancer Regiment.
W34: Aide-de-Camp to the Commander-in-Chief (a Captain)
W35: three caps (I missed the label).
W36: a second cabinet labelled the Battle of Warsaw. The rifles are a Lebel, a Moisin and a Mannlicher.
W37: a private of the 1st Legion Infantry Division.
W38: Tartar Lancer.
W39: 4th Lancer Regiment. The fabric for this appears to be German.
W40: Two Budennovkas and a Soviet flag (very faded from original red). Only the obverse can be seen. It is a very faded red, with a small white star in the centre with a very rough hammer and sickle on the star. Below that can be seen the unit's name "101ый Стрелковый Ролк".
Also in the background, but not visible in this picture appears to be some captured cap and tunic (judging by the red star on the cap).
W41: Life-Guard of the Commander-in-Chief.
W42: a cabinet labelled "Infantry", which seems to be largely post-1920. This is mostly the official 1919 uniform, which wasn't much worn until after the 1920 campaign.
The cabinet also included at least one Silesian insurgent. This may be the one to the left of the Woman Volunteer.
W44: a captain of the Volunteer Womens Legion. No indication of if this is from the 1920 period, but the rest of the cabinet is not, so perhaps it is later. (This tunic may be cut from English cloth.)
W45: the official M1919 uniform for a corporal. (With the little eagles on the buttons, braid around the neck and helmet, it wouldn't have been very common for the 1920 period.)
W46: a lieutenant of a Podhole Rifle unit from the post war period, but kept for the greatcoat and the odd hat. The officer mannekins either side are also post-war.
W47: There was a corresponding "Cavalry" cabinet to the "Infantry" one, but these were largely dress or post-war so I took no photos.
W48: I think this cabinet may have been labelled "The War in the East", but I'm not entirely sure.
W49: private of the Volunteer Army. He has an Enfield. The tunic seemed to be almost Russian coloured to me. The cloth strap attaches to a leather bag.
W50: General Sosnikowski's uniform in German grey, with a slightly greener cap.
W51: One of Piłsudski's uniforms in pike grey, though the cap is bluer.