December 11, 1699, Peter I founded St. Andrew's flag as the official flag of Russia

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About cops and fantasy.

And the color - easily traced historically:
"In 1848. Ruthenians - Ukrainians in Lviv have created a representative body and authority of national governments - Head Russian parliament. Commission of the Parliament May 18, 1848 , it was decided : to consider " the banner of the Russian land - a lion, and colors - yellow and blue."
As the prototype was made standard, known in history as veksillografii " Galician Lion" : golden crowned lion " vosstayuschy " on a blue (azure) background , climbing the golden rock.

In the description of Polish military units ( banners ), participated in the Battle of Grunwald in 1415 , twelve issues banner called the "land of Leopolskoy ( Lviv ), had a yellow flag at the lion, vshodyaschego like a rock , on an azure field ."

In addition to Lviv , pay attention to the colors of coats of arms of cities of Ukraine .

I think besides the banners of the Cossacks on the Black Sea last figure , and this is sufficient to determine , from which went to color.