After the peace, the French decided to colonise the "Isles Malouines" (Falkland Islands).
These islands were at that time almost unknown.
At his own expense, Bougainville undertook the task of resettling Acadians who had been deported to France by the British because of their refusal to sign loyalty oaths.

On 15 September 1763, Bougainville set out from France with the frigate L'Aigle (Eagle) (captained by Nicolas Pierre Duclos-Guyot) and the sloop Le Sphinz (Sphinx) (captained by François Chenard de la Giraudais).
This expedition included the naturalist and writer Antoine-Joseph Pernety (known as Dom Pernety), the priest and chronicler accompanying the expedition, together with the engineer and geographer Lhuillier de la Serre.

The expedition arrived in late January 1764 in French Bay (later renamed Berkeley Sound).
They landed at Port Louis named after King Louis XV.
A formal ceremony of possession of the Islands was held on 5 April 1764, after which Bougainville and Pernety returned to France.
Louis XV formally ratified possession on 12 September 1764.

Although the French colony did not number more than 150 people, for financial motivations (Bougainville having paid for the expeditions) and diplomatic reasons (Spain feared that the Falklands would become a rear base to attack her Peruvian gold), Bougainville was ordered by the French government to dismantle his colony and sell it to the Spanish.
Bougainville received 200,000 francs in Paris and an additional 500,000 francs in Buenos Aires.
Spain agreed to maintain the colony in Port Louis, thus preventing Britain from claiming title to the islands.
Spain had claimed dominion before the French settlement in association with its colonies on the mainland.
On 31 January 1767 at Río de la Plata, Bougainville met Don Felipe Ruiz Puente, commanding the frigate La Esmeralda and La Liebre ("the Hare") and future governor of Islas Malvinas, to transfer possession and evacuate the French population.

Bougainville wrote: 
It was not before 1766, that the English sent a colony to settle in Port de la Croisade, which they had named Port Egmont; and captain Macbride, of the Jason frigate, came to our settlement the same year, in the beginning of December.
He pretended that these parts belonged to his Britannic majesty, threatened to land by force, if he should be any longer refused that liberty, visited the governor, and sailed away again the same day.
After the peace, the French decided to colonise the "Isles Malouines" (Falkland Islands). These islands were at that time almost unknown. At his own expense, Bougainville undertook the task of resettling Acadians who had been deported to France by the British because of their refusal to sign loyalty oaths.
On 15 September 1763, Bougainville set out from France with the frigate L'Aigle (Eagle) (captained by Nicolas Pierre Duclos-Guyot) and the sloop Le Sphinz (Sphinx) (captained by François Chenard de la Giraudais). This expedition included the naturalist and writer Antoine-Joseph Pernety (known as Dom Pernety), the priest and chronicler accompanying the expedition, together with the engineer and geographer Lhuillier de la Serre.
The expedition arrived in late January 1764 in French Bay (later renamed Berkeley Sound). They landed at Port Louis named after King Louis XV. A formal ceremony of possession of the Islands was held on 5 April 1764, after which Bougainville and Pernety returned to France. Louis XV formally ratified possession on 12 September 1764.
Although the French colony did not number more than 150 people, for financial motivations (Bougainville having paid for the expeditions) and diplomatic reasons (Spain feared that the Falklands would become a rear base to attack her Peruvian gold), Bougainville was ordered by the French government to dismantle his colony and sell it to the Spanish. Bougainville received 200,000 francs in Paris and an additional 500,000 francs in Buenos Aires. Spain agreed to maintain the colony in Port Louis, thus preventing Britain from claiming title to the islands. Spain had claimed dominion before the French settlement in association with its colonies on the mainland. On 31 January 1767 at Río de la Plata, Bougainville met Don Felipe Ruiz Puente, commanding the frigate La Esmeralda and La Liebre ("the Hare") and future governor of Islas Malvinas, to transfer possession and evacuate the French population.
Bougainville wrote: 
It was not before 1766, that the English sent a colony to settle in Port de la Croisade, which they had named Port Egmont; and captain Macbride, of the Jason frigate, came to our settlement the same year, in the beginning of December. He pretended that these parts belonged to his Britannic majesty, threatened to land by force, if he should be any longer refused that liberty, visited the governor, and sailed away again the same day.
Louis Antoine de Bougainville