Why were the French armies called harbingers of liberty?

The French Revolution of 1789 was the first one to express nationalism.

1. The French armies spread the idea of freedom and nationalism.

2. By establishing Jacobin clubs, the French troops moved into Holland, Belgium, Switzerland, and Italy.

3. They aimed at liberating Europeans from dictatorship and authoritarianism.

The people of Brussels, Mainz, Milan, and Warsaw called the French armies as harbingers of liberty.