White represents peace and purity, as well as the White Eagle of the national coat of arms. Red represents the blood shed for the country and the red shield of the coat of arms.
History
The colors have been used since the 13th century. The bicolour flag was officially adopted as the national flag on August 1, 1919, after Poland regained its independence.
Construction
A 5:8 ratio. Two equal horizontal bands of white and red.