Coat of arms of the Second Polish Republic  (1919-1927)
The Second Polish Republic, or Second Commonwealth of Poland, or simply, interwar Poland, refers to Poland between the two World Wars; from the creation of an independent Polish state in the aftermath of World War I, to the invasion of Poland in 1939 by Nazi Germany, the Soviet Union, and the Slovak Republic, which marked the beginning of World War II.

The first Arms of the Second Republic were legally adopted on August 1, 1919 by the Parliament (Sejm), although it had been in use from October 1918 (Zakopane Republic).
Those Arms were modeled on the popular eagles from the times of the last king and symbols of the Napoleonic Duchy of Warsaw.
It is unknown who was the designer of the final artistic rendition of these particular White Eagles.
Source: http://www.loeser.us/flags/polish_note_4a.html#top