|Flag of Paris||Flag of France "Ancien Régime"|
The Paris militia (that used the city colors on its cockade) was very important to the storming of the Bastille. So, according to Marquis de Lafayette, during the French Revolution the white of the monarchy to the militia's cockade to create the national cockade and, then, the national flag. But there is always that history about "Liberty, Equality and Fraternity"...
The flag of France became influential, what made the vertical tricolor became a common pattern in vexillology. If there wasn't the French Revolution, the flags below, as well as many other, would never have existed.
|Flag of France||Flag of Spain|
The flag of Andorra is an example - but I wasn't necessarily talking about flags as much influenced by French tricolor. Andorra is a principality, but, in an only case in the world, it has two co-princes: the president of France and the bishop of the See of Urgell (in Catalonia, Spain). So the background of its flag is like the French flag, but with white changed to yellow to obtain Spanish red-yellow. Curiously, Catalonia province also uses red and yellow.
The flag of Belgium is, historically, based on the arms of the Duchy of Brabant, that, by the way, later became the coat of arms of Belgium. But you'll commonly find a popular alternate legend to its origin: black and yellow for Dutch-speaking Flanders and red and yellow for French-speaking Wallonia, although it's very anachronistic: Waloon flag was designed in 1913, and adopted in the 1975, and Flanders flag was only officialized in 1973, but the origins of Belgian flag dates from 19th century.
The explanation is so popular that it's present on the rationale, for example, to the nice-looking proposal for a new Belgian flag by Luc Swinnen.
Romania (and Moldova, too)
|Flag of Principality of Moldavia||Flag of Principality of Wallachia|
The colors of Romania have their own symbolism: blue for loyalty, perseverance and justice, yellow for generosity, red for bravery and strength. But there's a very famous legend that says that it's formed by Moldavian red and yellow with Wallachian yellow and blue. Transylvania joined before, but, as its flag was also blue-red-yellow, the flag wasn't changed.
The legend is disputed, as the colors were used in some contexts by Wallachia even before the union, but, if it's really true, the republic of Moldova, that adopted a flag based in Romanian one, have the Wallachian colors, too!
I like to find those connections that aren't dubious, as it demonstrates that flags aren't as trivial as we use to think. If you have any suggestion, critique, opinion, etc., you're welcome to comment!