That's incorrect. Monaco flag has different dimensions.
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It's white for the Polish eagle and red for the shield of Lithuania. From the days when the two territories were in union
Well, sort of. A few words are misspelled here but it has a good summary of the meaning of the colors.
[I]The Flag
by Mr. Jan Rękawek
Poland's national colors are white and red. On the flag these assume the form of two horizontal bands of equal width and length, the upper white and the lower, red.
The origin of the flag colors goes back to the Piast dynasty and relates to the White Eagle on a red field. However, the concept of the state flag in these colors dates from the 18th and 19th centuries.
In earlier times, red and white are found on royal standards and military flags, though not as separate hands.
In the 18th century, Polish soldiers began to wear white cockades on their caps. Thus white was the first color which had a specific meaning, it was the sign of the Polish soldier.The civilian population, in sympathy with the army, adopted white cockades during the insurrection of 1830-31. At that time, tricolor cockades (red, white and blue) [borrowed from French revolution - my remark] as well as red and white ones were also worn. This lack of uniformity induced the Sejm to pass a resolution on February 7, 1831, adopting the white and red cockade as official.It was the first legal act by the nation's supreme representatives regulating Poland's colors and making white and red the national colors. After the uprising was suppressed, the red and white cockades were outlawed by the Tsarist authorities, but the colors continued to be used wherever Poles in exile fought for the cause of freedom.
On November 11, 1918, a Warsaw University student. heralding the coming independence, raised a big white and red flag on the Radziwiil Palace, then the seat of the German occupational authority, and today, the residence of Poland's President. The following year, the Sejm of the resurgent Polish state adopted the white and red flag as the official design which remains unchanged to this day.
In many countries, including Poland, hut not the United States, the country's ensign differs somewhat from its flag. The ensign is the flag flown by warships at sea. On land, it is a symbol of government authority. Poland's ensign differs from its flag by having a White Eagle on a red shield in the middle of the white band. Moreover, the ensign used by the Polish Navy is swallowtailed, a characteristic of the warship ensigns of countries on the Baltic Sea.
The raising of the Star-Spangled Banner by the G-I's over Iwo Jima is a familiar American icon. Earlier, on May 18, 1944, an analogous scenario occuned in Italy, when, in one of the greatest battles of the Second World War, soldiers of the Polish Second Corps captured the Monte Cassino bastion, the pivot of the German defense system in Italy.
The Polish flag was proudly raised that day atop ruins of the monastery on Monte Cassino. It was a signal that the road to Rome had been opened.
While the raising of the Polish flag over Monte Cassino has been photographically immortalized, another event of momentous significance has not. Polish troops of the Kościuszko division, serving under Russian command, were the first to fight their way to the center of Berlin at the end of the World War II. There they raised the Polish flag over the Branderburg gate, only to have it taken down soon thereafter by the Soviets who replaced it with their own red banner.
The White and Red flag and the crowned White Eagle, symbols of sovereign Poland, remain the emblems of the Polish heritage which are traditionallly celebrated on May 3rd, Polands's Constitution Day.[/]
Flag of Poland
Flag of Monaco
As you can see the overall dimensions and the thickness of the stripes is different.