Question: When did the armed force in which Bertie Fisher served invade Saint Barthélemy?

full_context: Document 1: Norfolk Island: Norfolk Island has 174 native plants; 51 of them are endemic. At least 18 of the endemic species are rare or threatened. The Norfolk Island palm (Rhopalostylis baueri) and the smooth tree-fern (Cyathea brownii), the tallest tree-fern in the world, are common in the Norfolk Island National Park but rare elsewhere on the island. Before European colonization, most of Norfolk Island was covered with subtropical rain forest, the canopy of which was made of Araucaria heterophylla (Norfolk Island pine) in exposed areas, and the palm Rhopalostylis baueri and tree ferns Cyathea brownii and C. australis in moister protected areas. The understory was thick with lianas and ferns covering the forest floor. Only one small tract (5 km2) of rainforest remains, which was declared as the Norfolk Island National Park in 1986.
Document 2: Saint Barthélemy: Agricultural production on the island is difficult given the dry and rocky terrain, but the early settlers managed to produce vegetables, cotton, pineapples, salt, bananas and also fishing. Sweet potato is also grown in patches. The islanders developed commerce through the port of Gustavia. Duty-free port attractions, retail trade, high-end tourism (mostly from North America) and its luxury hotels and villas have increased the island's prosperity, reflected in the high standard of living of its citizens.
Document 3: Saint Barthélemy: Other trees of note include the royal palm, sea grape trees in the form of shrubs on the beaches and as 5 to 7 m trees in the interior areas of the island, aloe or aloe vera (brought from the Mediterranean), the night blooming cereus, mamillaria nivosa, yellow prickly pear or barbary fig which was planted as barbed wire defences against invading British army in 1773, Mexican cactus, stapelia gigantea, golden trumpet or yellow bell which was originally from South America, bougainvillea and others.
Document 4: Standish O'Grady Roche: Sir Standish O'Grady Roche, 4th Baronet, DSO (or Standish O'Grady-Roche) (13 March 1911 – 2 April 1977) of Ireland, was commanding officer of the destroyer HMS "Beaufort" in the World War II Second Battle of Sirte on 22 March 1942. He earned the Distinguished Service Order and Croix de Guerre while protecting convoys near Malta. He also served as aide-de-camp to the Governor-General of New Zealand through January 1938 while a Royal Navy lieutenant.
Document 5: Saint Barthélemy: As the terrain is generally arid, the hills have mostly poor soil and support only cacti and succulent plants. During the rainy season the area turns green with vegetation and grass. The eastern part of the island is greener as it receives more rainfall. A 1994 survey has revealed several hundred indigenous species of plants including the naturalized varieties of flora; some growing in irrigated areas while the dry areas are dominated by the cacti variety. Sea grapes and palm trees are a common sight with mangroves and shrubs surviving in the saline coastal swamps. Coconut palm was brought to the island from the Pacific islands. Important plants noted on the island are:
Document 6: Saint Barthélemy: Marine mammals are many, such as the dolphins, porpoises and whales, which are seen here during the migration period from December till May. Turtles are a common sight along the coastline of the island. They are a protected species and in the endangered list. It is stated that it will take 15–50 years for this species to attain reproductive age. Though they live in the sea, the females come to the shore to lay eggs and are protected by private societies. Three species of turtles are particularly notable. These are: The leatherback sea turtles which have leather skin instead of a shell and are the largest of the type found here, some times measuring a much as 3 m (average is about 1.5 m) and weighing about 450 kg (jellyfish is their favourite diet); the hawksbill turtles, which have hawk-like beaks and found near reefs, generally about 90 cm in diameter and weigh about 60 kg and their diet consists of crabs and snails; and the green turtles, herbivores which have rounded heads, generally about 90 cm in diameter and live amidst tall sea grasses.
Document 7: Saint Barthélemy: Saint-Barthélemy has a marine nature reserve, known as the Reserve Naturelle that covers 1.200 ha, and is divided into 5 zones all around the island to form a network of protected areas. The Reserve includes the bays of Grand Cul de Sac, Colombier, Marigot, Petit Cul de Sac, Petite Anse as well as waters around offshore rocks such as Les Gross Islets, Pain de Sucre, Tortue and Forchue. The Reserve is designed to protect the islands coral reefs, seagrass and endangered marine species including sea turtles. The Reserve has two levels of protection, the yellow zones of protection where certain non-extractive activities, like snorkeling and boating, are allowed and the red zones of high protection where most activities including SCUBA are restricted in order to protect or recover marine life. Anchoring is prohibited in the Reserve and mooring buoys are in place in some of the protected bays like Colombier
Document 8: Arthur Hartley: During the Second World War Hartley was seconded to the government where he was involved in the development of the bombsight which sank the "Tirpitz", the Operation Pluto pipeline project and the FIDO fog dispersion system. Following the war he was rewarded with an appointment as Commander of the Order of the British Empire (CBE), a United States Medal of Freedom and £9000 cash. He retired from Anglo-Iranian in 1951 and was elected president of the Institution of Mechanical Engineers. He was elected president of the Institution of Civil Engineers in 1959, but died three months into his tenure.
Document 9: Frederick Fryer: He served in the Second Boer War and the First World War, commanding his regiment and two mounted brigades. In later life he became a Deputy Lieutenant of Dorset and a Justice of the Peace.
Document 10: Mario Berti: Mario Berti (1881–1964) was an Italian officer during World War I and a general in the Spanish Civil War and World War II.
Document 11: Ludwig Bieringer: Ludwig Bieringer (1892–1975) was a German general during World War II. A lifelong professional soldier, he served his country as a junior officer in World War I, a staff officer in the inter-war period and a brigade-level commander during World War II.
Document 12: Bermuda: Bermudians served in the British armed forces during both World War I and World War II. After the latter, Major-General Glyn Charles Anglim Gilbert, Bermuda's highest-ranking soldier, was instrumental in developing the Bermuda Regiment. A number of other Bermudians and their descendants had preceded him into senior ranks, including Bahamian-born Admiral Lord Gambier, and Bermudian-born Royal Marines Brigadier Harvey. When promoted to Brigadier at age 39, following his wounding at the Anzio landings, Harvey became the youngest-ever Royal Marine Brigadier. The Cenotaph in front of the Cabinet Building (in Hamilton) was erected in tribute to Bermuda's Great War dead (the tribute was later extended to Bermuda's Second World War dead) and is the site of the annual Remembrance Day commemoration.
Document 13: Bertie Fisher: Lieutenant General Sir Bertie Drew Fisher, KCB, CMG, DSO (13 July 1878 – 24 July 1972) was a British Army General during World War II.
Document 14: Harold Henry Fisher: Fisher was born in Morristown, Vermont; he received an AB from the University of Vermont in 1911. He served as a field artillery captain during World War I, and was appointed chief of the Historical Department of American Relief Administration during the post-war famine in Eastern Europe and Russia. His collection of Tsarist and Bolshevik documents subsequently became a permanent part of the Hoover Institution's holdings.
Document 15: Legends of the coco de mer: Nut and tree of the coco de mer, a rare species of palm tree native to the Seychelles archipelago in the Indian Ocean, is the subject of various legends and lore. Coco de mer is endemic to the Seychelles islands of Praslin and Curieuse. Before the Seychelles were discovered and settled, nuts of this species were sometimes carried by the ocean currents to distant shores, such as those of the Maldives, where the tree was unknown. These floating nuts did not germinate. The exceptional size and suggestive form of the nut, the circumstances of its discovery, and some unusual qualities of the trees have given rise to several legends.
ground_truth: 1773
sub_queries: Bertie Fisher >> military branch Answer: British Army
When did British Army invade the island? Answer: 1773