As the news of the revolution spread acroos Europe, monarchs in the German kingdoms and the Austrian Empire began to worry about the stability of their own governments. The nobles who had fled France, tried to convince the leaders of these governments that their own rule would be threatened unless the revolution in France was destroyed before it could spread. In the summer of 1792 France went to war with Austria and Prussia (the largest German kingdom).
From the start the war went poorly for the new French government. The fear that the entire revolution could be in danger caused more radical members of the Assembly to gain power. They then abolished the monarchy altogether and established France as a replublic. The National Assembly then became the National Convention and it continued to pass legislative which furture did away with aspects of the old French society. It also established universal suffrage which meant that all men could vote whether they owned property or not.