Poland fought for preserving its independence and establishing its final borders in 1918-1921, and many people died in those conflicts, especially during the Polish-Soviet War. In 1934 they published a book "List of casualties of the Polish Army in wars of 1918-1920", according to that book the total number of casualties of the Polish Army (but it does not include losses in uprisings) in that period were 255,846 dead, wounded and missing (including 101,124 dead or missing). The bloodiest month was August 1920 with 50,079 casualties (1/5 of the total).

This list is not fully complete, as authors of that 1934 book mentioned on page 12.

Polish casualties in the battle of Warsaw (12-25 August 1920) were 14,500 dead or missing and 22,000 wounded.

^^^
Polish monthly losses according to that book (doesn't include insurgents in uprisings, they weren't part of the Army):

Month - number of dead, missing without a trace and wounded:

1918

XI - 1642
XII - 856

1919

I - 4110
II - 2401
III - 4624
IV - 3507
V - 4311
VI - 8214
VII - 5141
VIII - 4586
IX - 4086
X - 3272
XI - 1715
XII - 2186

1920

I - 4624
II - 5814
III - 6292
IV - 6860
V - 19261
VI - 26601
VII - 34198
VIII - 50079
IX - 29146
X - 12880
XI - 4907
XII - 3061

Unknown month - 1472

Total - 255846

^^^ Compare to how the frontline was changing over time:



Check also my thread about Posen Uprising in 1918-1919:

https://www.theapricity.com/forum/sh...=1#post5628650

Soon after the uprising Polish casualties were reported as 1714 or 1784 dead. Few years ago further research established that those initial reports were incomplete. The new list of dead and missing contains 2289 people, including some with unknown surnames. It might still be incomplete, so it is estimated that Polish insurgents lost up to 2500 dead and missing. I don't know how high were German casualties.