In November 1830, the National Congress of Belgium was established to create a constitution for the new state.
The Congress decided that Belgium would be a popular, constitutional monarchy.
On 7 February 1831, the Belgian Constitution was proclaimed.
However, no actual monarch yet sat on the throne.

The Congress refused to consider any candidate from the Dutch ruling house of Orange-Nassau.
Eventually the Congress drew up a shortlist of three candidates, all of whom were French.
This itself led to political opposition, and Leopold of Saxe-Coburg, who had been considered at an early stage but dropped due to French opposition, was proposed again.
On 22 April 1831, Leopold was approached by a Belgian delegation at Marlborough House to officially offer him the throne.
At first reluctant to accept, he eventually took up the offer, and after an enthusiastic popular welcome on his way to Brussels, Leopold I of Belgium took his oath as king on 21 July 1831.

21 July is generally used to mark the end of the revolution and the start of the Kingdom of Belgium.
It is celebrated each year as Belgian National Day.
In November 1830, the National Congress of Belgium was established to create a constitution for the new state. The Congress decided that Belgium would be a popular, constitutional monarchy. On 7 February 1831, the Belgian Constitution was proclaimed. However, no actual monarch yet sat on the throne.
The Congress refused to consider any candidate from the Dutch ruling house of Orange-Nassau. Eventually the Congress drew up a shortlist of three candidates, all of whom were French. This itself led to political opposition, and Leopold of Saxe-Coburg, who had been considered at an early stage but dropped due to French opposition, was proposed again. On 22 April 1831, Leopold was approached by a Belgian delegation at Marlborough House to officially offer him the throne. At first reluctant to accept, he eventually took up the offer, and after an enthusiastic popular welcome on his way to Brussels, Leopold I of Belgium took his oath as king on 21 July 1831.
21 July is generally used to mark the end of the revolution and the start of the Kingdom of Belgium. It is celebrated each year as Belgian National Day.
Belgian Revolution