On 20 June 1789, following the declaration by the King that the National Assembly was illegal, the hall that was being used as the premises of the Assembly was locked by royal decree. In retaliation, the Assembly walked to a nearby indoor tennis court and took an oath, as proposed by Jean-Joseph Mounier:

“never to separate until an acceptable constitution was created for France“

It was adopted by majority rule, in a democratic fashion, with dissension accepted as one individual, Martin d’Auch, did not take the oath.

The Tennis Court Oath marked the first formal act of defiance against the monarchy, sparking revolutionary action, and introduced the idea of establishing a constitution for France.

See Also

National Assembly