who designed it?
Giuseppe Compagnoni
Flag of Italy
The first red, white and green national flag of a sovereign Italian state was instead adopted, as mentioned, on 7 January 1797, when the Fourteenth Parliament of the Cispadane Republic, on the proposal of deputy Giuseppe Compagnoni of Lugo, decreed "to make universal the ... standard or flag of three colours, green, white, and red ...": 
what do the colors of the italian flag stand for The idealistic meaning - the green represents hope, the white represents faith and the red represents love.
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Flag of Italy [SEP] The birth of the flag of Italy
Following the adoption by the Bolognese congregation, the Italian flag became a political symbol of the struggle for the independence of Italy from foreign powers, supported by its use also in the civil sphere. The following adoption of the Italian flag by a state body, the Cispadan Republic, was inspired by this Bolognese banner, linked to a municipal reality and therefore still having a purely local scope, and to the previous military banners of the Lombard Legion and Italian Legion, which took place on 7 January 1797. The first red, white and green national flag of a sovereign Italian state was instead adopted, as mentioned, on 7 January 1797, when the Fourteenth Parliament of the Cispadane Republic, on the proposal of deputy Giuseppe Compagnoni of Lugo, decreed "to make universal the ...