Belley was said to have been born on 1 July 1746 or 1747 on the island of Gorée, Senegal, but the dates of his birth and death are uncertain. At the age of two, he was sold to slavers sailing for the French colony of Saint-Domingue. With his savings, he later bought his freedom.
In 1791, the enslaved Africans of Saint-Domingue began the Haitian Revolution, aimed at the overthrow of the colonial regime. As their fellow revolutionaries in France thought the Declaration of the Rights of Man of 1789, they began to see that slavery would need to be abolished.
In 1793, Bellay was a Captain of infantry, fought against the colonists of Saint-Domingue and was six times wounded. On 24 September 1793, he was one of three members (deputés) elected to the French National Convention by the northern region of Saint-Domingue, together with Jean-Baptiste Mills, a mulatto, and Louis-Pierre Dufaÿ, a European, thus becoming the first black deputy to take a seat in the Convention. On 3 February 1794, he spoke in a debate in the Convention when it decided unanimously to abolish slavery.
However, the formal abolition of slavery did not disarm the European colonists’ supporters, and although he was recognized as a full citizen of the Republic, Belley had to struggle against racist insinuations. He was an active spokesman for people of colour. When Benoît Gouly, a pro-slavery deputy from Mauritius in the Indian Ocean, called for special laws for the colonies, Belley denounced a pressure group of colonists meeting at the Hôtel Massiacin a speech published under the title Le Bout d’oreille des colons, ou le système de l’Hôtel Massiac mis à jour par Gouly He succeeded for a time in maintaining the Republican principle of equality between people in France and in its colonies, whatever their colour.
In a declaration of age and marital status for the representatives of Saint-Domingue in the Convention, Belley says that he was born at Gorée, is forty-eight years old, has never left the territory of the Republic, and has lived forty six years at Cap-Français. In a ‘declaration of fortune’ dated at Paris on 10 Vendémiaire, Year 4 of the Republic (viz., 1 October 1795), Belley declares that from the Republic he has only his ‘emoluments’, that he has bought no property, and that he owns only the contents of his room.
Belley remained as a Convention member until 1797, when he lost his seat.He returned to Saint-Domingue with Charles Leclerc’s expedition of 1802 as an officer of gendarmes, but he was arrested, sent back to France and imprisoned in the fortress of Belle Île. He was still being held prisoner there in 1805 when he wrote to Isaac Louverture, the son of Toussaint Louverture. He died later the same year.