The design of the U.S. flag was derived from designs used for flags at the beginning of the American Revolution. On June 14, 1777, Congress declared the flag to be 13 alternating red and white stripes with a union of 13 white stars in a blue field. In 1794, after Kentucky and Vermont joined the Union, Congress added two stars and two stripes. In 1818, when five more states had joined, Congress again changed the design to 13 stripes, representing the original 13 states, and 20 stars, with a provision that an additional star be added on the admission of each new state.

Although popular tradition has invested the colors of the flag with symbolism--red for valor, white for liberty or purity, and blue for justice, loyalty, and perseverance--there is no document that historians can point to that gives this symbolism official standing.

The New England Pine Tree Flag had been in use for nearly 90 years when it was flown at the Battle of Bunker Hill in 1775.


This naval flag, used 1775 to 1776, combined two American symbols of liberty--stripes and the rattlesnake.

 

The Continental Colors, used by George Washington's army after Jan. 1, 1775, combined the Union Jack, the national emblem of the mother country, with the stripes of liberty.

 

This flag ("Betsy Ross") was authorized by Congress on June 14, 1777. The legislation did not specify how the stars should be arranged.

 

"That the flag of the thirteen United States be 13 stripes alternate red and white, that the union be 13 stars, white in a blue field representing a new constellation." --The First Flag Act, June 14, 1777

 

 

The 15-star, 15-stripe flag was authorized by Congress in 1795. This flag flew over Fort McHenry and became known as the Star-Spangled Banner.

 

The First Flag Act - June 14, 1777
"That the flag of the thirteen United States be 13 stripes alternate red and white, that the union be 13 stars, white in a blue field representing a new constellation."
* The 13-star, 13-stripe flags are from this period.


The Second Flag Act - May 1, 1795

"That the flag of the United States be fifteen stripes, alternate red and white and that the union be fifteen stars, white in a blue field."
* The 15-star, 15-stripe flag (like the Star-Spangled Banner) is from this period.


The Flag Act of 1818
"That from and after the fourth day of July next, the flag of the United States be thirteen horizontal stripes, alternate red and white; that the union be twenty stars, white in a blue field. And be it further enacted, that on the admission of every state into the Union, one star be added to the union of the flag; and that such addition shall take effect on the fourth of July next succeeding such admission."
* The 50-star, 13-stripe flag (in use since 1960) is from this period.

The Flag History Information posted here is from The Smithsonian's Website.

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States and Their Dates of Admission to the Union:
State Date Admitted to Union
 1DelawareDecember 7, 1787
 2PennsylvaniaDecember 12, 1787
 3New JerseyDecember 18, 1787
 4GeorgiaJanuary 2, 1788
 5ConnecticutJanuary 9, 1788
 6MassachusettsFebruary 6, 1788
 7MarylandApril 28, 1788
 8South CarolinaMay 23, 1788
 9New HampshireJune 21, 1788
 10VirginiaJune 25, 1788
 11New YorkJuly 26, 1788
 12North CarolinaNovember 21, 1789
 13Rhode IslandMay 29, 1790
 14VermontMarch 4, 1791
 15KentuckyJune 1, 1792
 16TennesseeJune 1, 1796
 17OhioMarch 1, 1803
 18LouisianaApril 30, 1812
 19IndianaDecember 11, 1816
 20MississippiDecember 10, 1817
 21IllinoisDecember 3, 1818
 22AlabamaDecember 14, 1819
 23MaineMarch 15, 1820
 24MissouriAugust 10, 1821
 25ArkansasJune 15, 1836
 26MichiganJanuary 26, 1837
 27FloridaMarch 3, 1845
 28TexasDecember 29, 1845
 29IowaDecember 28, 1846
 30WisconsinMay 29, 1848
 31CaliforniaSeptember 9, 1850
 32MinnesotaMay 11, 1858
 33OregonFebruary 14, 1859
 34KansasJanuary 29, 1861
 35West VirginiaJune 20, 1863
 36NevadaOctober 31, 1864
 37NebraskaMarch 1, 1867
 38ColoradoAugust 1, 1876
 39North DakotaNovember 2, 1889
 40South DakotaNovember 2, 1889
 41MontanaNovember 8, 1889
 42WashingtonNovember 11, 1889
 43IdahoJuly 3, 1890
 44WyomingJuly 10, 1890
 45UtahJanuary 4, 1896
 46OklahomaNovember 16, 1907
 47New MexicoJanuary 6, 1912
 48ArizonaFebruary 14, 1912
 49AlaskaJanuary 3, 1959
 50HawaiiAugust 21, 1959