Question

how was France declared as a constitutional monarchy​

Answer 1

As such, France declared war on Austria in 1792. ... Thus, the Constitutional Monarchy came to an end, and the First French Republic was declared. The French Constitutional Monarchy was something of a failure

Answer 2

Constitution of 1791, French constitution created by the National Assembly during the French Revolution. It retained the monarchy, but sovereignty effectively resided in the Legislative Assembly, which was elected by a system of indirect voting. The franchise was restricted to “active” citizens who paid a minimal sum in taxes; about two-thirds of adult men had the right to vote for electors and to choose certain local officials directly. The constitution lasted less than a year.

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