With the hideous terrorist attacks in Paris, it is natural to want to show some kind of support for France and the Parisians. I was in Paris not too long ago, and the people were very friendly, helpful and showed support for the United States, especially in the Normandy area where D Day occurred.
People around the free world are flying the French tri-color flag along with their own. It's a beautiful sentiment.
I looked into another interesting, if not lovely, way to show alliance during the 18th Century. The "Cockade", or knot of ribbons, arranged in a circular shape and worn on the side of a man's tricorne hat, or on lapels or in the hair of women. The cockade would generally show, at that time, allegiance to some political faction, their rand, or as part of a servant's livery.
In pre-revolutionary France, the cockade of the Bourbons was all white. In Great Britian, supporters of the Jacobites wore them white, and in the Hanoverian monarchy, they were black.
In 1780, a blue cockade was worn as a symbol of anti-government feelings worn by rioters in the Gordon Riots.
During the American Revolution, the Continental army wore them in various colors, until General George Washington stated
"As the Continental Army has unfortunately no uniforms, and consequently many inconveniences must arise from not being able to distinguish the commissioned officers from the privates, it is desired that some badge of distinction be immediately provided; for instance that the field officers may have red or pink colored cockades in their hats, the captains yellow or buff, and the subalterns green."
Eventually the Continental Army reverted to a black cockade that they inherited from the British. When France became a US ally, the Army pinned the white cockade of the French Ancien Regime onto the old black cockade. The French in turn pinned a black circle of ribbons to their white. These became known as the "Union Cockade". Later on, the French would develop the tri-color (red, white, blue - the arms of Paris) cockade, known as the "Tricolore".
And there you have it, the origins of a very pretty as well as powerful symbol of allegiance. Makes me want to sew one up right now!