#OTD in 1907, the Act of June 13, 1907, P.L. 560, No. 373, designated the official PA flag, saying, the flag of the Commonwealth of Pennsylvania shall be of blue, same color as blue field in the flag of the United States, embroidered with the State Coat of Arms.
ALT The image shows the Pennsylvania state flag, featuring a blue field with a central coat of arms, flanked by black horses, an eagle atop, and a red ribbon reading "Virtue, Liberty, and Independence."