Flags are almost as old as civilization itself. Imperial Egypt as well as the armies of Babylon, Chaldea, and Assyria followed the colors of their kings. The Old Testament frequently mentions banners and standards. Until comparatively recent years, the flags that identified nations usually were based on the personal or family heraldry of the reigning monarch or ruling nobleman. As autocracies faded or disappeared, dynastic colors were no longer popular and national flags, as thought of today, came into being. These national flags, such as the Union Jack of Great Britain, the Tricolor of France, and the Stars and Stripes, are relatively new to history. Many flags of different designs were present in parts of the American colonies before the Revolution. When the struggle for independence united the colonies, there grew a desire for a single flag to represent the new nation. The first flag borne by the Army as a representative of the 13 colonies was the Grand Union flag. It was raised over the Continental Army at Cambridge, Massachusetts, on 2 January 1776. That flag had the familiar 13 stripes (red and white) of the present flag, but the blue square contained the Crosses of St. George and St. Andrew from the British flag.

The Stars and Stripes was born on 14 June 1777, two years to the day after the birth of the Army. On that date, Congress resolved that the flag of the United States be 13 stripes, alternate red and white, and that the union be 13 stars, white in a blue field, representing a new constellation. The arrangement of the stars on the blue field was not specified.

According to some historians, the Stars and Stripes was first raised over Fort Stanwix, New York, on 3 August 1777. In that Army version of the flag, the stars were arranged in a circle. (The Navy version had the stars arranged to form crosses similar to the British flag.)

When Vermont and Kentucky joined the Union, the flag was modified so that there were 15 stars and 15 stripes. It was that flag, flying triumphantly over Fort McHenry, Maryland, on 13 and 14 September 1814, inspiring Francis Scott Key to compose the verses of "The Star-Spangled Banner." That flag was the national banner from 1795 until 1818. Thus, when it was raised over Tripoli by the Marines in 1805, it was the first United States flag to be hoisted over conquered territory in the Old World. Later, it was flown by General Andrew Jackson at the Battle of New Orleans.

Realizing that adding a stripe for each new state would soon spoil the appearance of the flag, Congress passed a law in 1818 fixing the number of stripes at 13 and providing for the addition of a star in the Blue Union for each new state. The star is to be added and the new flag to become official on the Fourth of July following the admission of the new state to the Union. It was not until shortly before the Civil War that the Stars and Stripes actually became the National Color.

From the earliest times, warriors used a banner or other symbol to identify specific units and to serve as a rallying point for troops. In medieval days, the standard or banner was used to signal a general assault, which was generated by a cry of "Advance your banners."

After the Battle of Waterloo, a British sergeant wrote "About 4 o’clock I was ordered to the Colours; this, although I was used to warfare as much as anyone, was a job I did not at all like. But still I went as boldly to work as I could. There had been before me that day 14 sergeants already killed and wounded and the staff and the Colours almost cut to pieces."

Before the Civil War, in lieu of a National Color, the US soldiers carried a blue silk color on which was embroidered the arms of the United States, and an American eagle bearing a shield on its breast, and in its talons an olive branch and arrows, signifying peace and war. After the National Color was authorized, the organizational color with the eagle became the regimental color. Because of the high casualty rate among the members of the Color party, plus the advent of modern weapons, the time-honored practice of carrying the Colors in battle was discontinued. Today, the Colors, with battle streamers attached, join their unit in formations during ceremonies to signify their presence during past battles.