Question: What language was used by the people of the British Isles under the empire that, in the 1st Century B.C., acquired the sunniest country in the world as a colony?

full_context: Document 1: Hellenistic period: Ptolemy, a somatophylax, one of the seven bodyguards who served as Alexander the Great's generals and deputies, was appointed satrap of Egypt after Alexander's death in 323 BC. In 305 BC, he declared himself King Ptolemy I, later known as "Soter" (saviour) for his role in helping the Rhodians during the siege of Rhodes. Ptolemy built new cities such as Ptolemais Hermiou in upper Egypt and settled his veterans throughout the country, especially in the region of the Faiyum. Alexandria, a major center of Greek culture and trade, became his capital city. As Egypt's first port city, it was the main grain exporter in the Mediterranean.
Document 2: British Isles: Hiberni (Ireland), Pictish (northern Britain) and Britons (southern Britain) tribes, all speaking Insular Celtic, inhabited the islands at the beginning of the 1st millennium AD. Much of Brittonic-controlled Britain was conquered by the Roman Empire from AD 43. The first Anglo-Saxons arrived as Roman power waned in the 5th century and eventually dominated the bulk of what is now England. Viking invasions began in the 9th century, followed by more permanent settlements and political change—particularly in England. The subsequent Norman conquest of England in 1066 and the later Angevin partial conquest of Ireland from 1169 led to the imposition of a new Norman ruling elite across much of Britain and parts of Ireland. By the Late Middle Ages, Great Britain was separated into the Kingdoms of England and Scotland, while control in Ireland fluxed between Gaelic kingdoms, Hiberno-Norman lords and the English-dominated Lordship of Ireland, soon restricted only to The Pale. The 1603 Union of the Crowns, Acts of Union 1707 and Acts of Union 1800 attempted to consolidate Britain and Ireland into a single political unit, the United Kingdom of Great Britain and Ireland, with the Isle of Man and the Channel Islands remaining as Crown Dependencies. The expansion of the British Empire and migrations following the Irish Famine and Highland Clearances resulted in the distribution of the islands' population and culture throughout the world and a rapid de-population of Ireland in the second half of the 19th century. Most of Ireland seceded from the United Kingdom after the Irish War of Independence and the subsequent Anglo-Irish Treaty (1919–1922), with six counties remaining in the UK as Northern Ireland.
Document 3: British Isles: The earliest known references to the islands as a group appeared in the writings of sea-farers from the ancient Greek colony of Massalia. The original records have been lost; however, later writings, e.g. Avienus's Ora maritima, that quoted from the Massaliote Periplus (6th century BC) and from Pytheas's On the Ocean (circa 325–320 BC) have survived. In the 1st century BC, Diodorus Siculus has Prettanikē nēsos, "the British Island", and Prettanoi, "the Britons". Strabo used Βρεττανική (Brettanike), and Marcian of Heraclea, in his Periplus maris exteri, used αἱ Πρεττανικαί νῆσοι (the Prettanic Isles) to refer to the islands. Historians today, though not in absolute agreement, largely agree that these Greek and Latin names were probably drawn from native Celtic-language names for the archipelago. Along these lines, the inhabitants of the islands were called the Πρεττανοί (Priteni or Pretani). The shift from the "P" of Pretannia to the "B" of Britannia by the Romans occurred during the time of Julius Caesar.
Document 4: British Isles: At the time of the Roman Empire, about two thousand years ago, various tribes, which spoke Celtic dialects of the Insular Celtic group, were inhabiting the islands. The Romans expanded their civilisation to control southern Great Britain but were impeded in advancing any further, building Hadrian's Wall to mark the northern frontier of their empire in 122 AD. At that time, Ireland was populated by a people known as Hiberni, the northern third or so of Great Britain by a people known as Picts and the southern two thirds by Britons.
Document 5: Namibia: Typically the sub-Tropical High Pressure Belt, with frequent clear skies, provides more than 300 days of sunshine per year. It is situated at the southern edge of the tropics; the Tropic of Capricorn cuts the country about in half. The winter (June – August) is generally dry, both rainy seasons occur in summer, the small rainy season between September and November, the big one between February and April. Humidity is low, and average rainfall varies from almost zero in the coastal desert to more than 600 mm in the Caprivi Strip. Rainfall is however highly variable, and droughts are common. The last[update] bad rainy season with rainfall far below the annual average occurred in summer 2006/07.
Document 6: Alexander the Great: Alexander the Great Basileus of Macedon, Hegemon of the Hellenic League, Shahanshah of Persia, Pharaoh of Egypt, Lord of Asia ``Alexander fighting king Darius III of Persia '', Alexander Mosaic, Naples National Archaeological Museum King of Macedonia Reign 336 -- 323 BC Predecessor Philip II Successor Alexander IV Philip III Pharaoh of Egypt Reign 332 -- 323 BC Predecessor Darius III Successor Alexander IV Philip III King of Persia Reign 330 -- 323 BC Predecessor Darius III Successor Alexander IV Philip III King of Asia Reign 331 -- 323 BC Predecessor New office Successor Alexander IV Philip III 20 or 21 July 356 BC Pella, Macedon, Ancient Greece 10 or 11 June 323 BC (aged 32) Babylon Spouse Roxana of Bactria Stateira II of Persia Parysatis II of Persia Issue Alexander IV Full name Alexander III of Macedon Greek Μέγας Ἀλέξανδρος (Mégas Aléxandros, Great Alexander) Ἀλέξανδρος ὁ Μέγας (Aléxandros ho Mégas, Alexander the Great) Dynasty Argead Father Philip II of Macedon Mother Olympias of Epirus Religion Greek polytheism
Document 7: Egypt: The last ruler from the Ptolemaic line was Cleopatra VII, who committed suicide following the burial of her lover Mark Antony who had died in her arms (from a self-inflicted stab wound), after Octavian had captured Alexandria and her mercenary forces had fled. The Ptolemies faced rebellions of native Egyptians often caused by an unwanted regime and were involved in foreign and civil wars that led to the decline of the kingdom and its annexation by Rome. Nevertheless, Hellenistic culture continued to thrive in Egypt well after the Muslim conquest.
Document 8: Roman Britain: Julius Caesar invaded Britain in 55 and 54 BC as part of his Gallic Wars. The Britons had been overrun or culturally assimilated by other Celtic tribes during the British Iron Age and had been aiding Caesar's enemies. He received tribute, installed a friendly king over the Trinovantes, and returned to Gaul. Planned invasions under Augustus were called off in 34, 27, and 25 BC. In 40 AD, Caligula assembled 200,000 men at the Channel, only to have them gather seashells. Three years later, Claudius directed four legions to invade Britain and restore an exiled king over the Atrebates. The Romans defeated the Catuvellauni, and then organized their conquests as the Province of Britain (Latin: Provincia Britannia). By the year 47, the Romans held the lands southeast of the Fosse Way. Control over Wales was delayed by reverses and the effects of Boudica's uprising, but the Romans expanded steadily northward.
Document 9: History of Egypt: In 332 BC, Macedonian ruler Alexander the Great conquered Egypt as he toppled the Achaemenids and established the Hellenistic Ptolemaic Kingdom, whose first ruler was one of Alexander's former generals, Ptolemy I Soter. The Ptolemies had to fight native rebellions and were involved in foreign and civil wars that led to the decline of the kingdom and its final annexation by Rome. The death of Cleopatra ended the nominal independence of Egypt resulting in Egypt becoming one of the provinces of the Roman Empire.
Document 10: Tibet: The atmosphere is severely dry nine months of the year, and average annual snowfall is only 18 inches (46 cm), due to the rain shadow effect. Western passes receive small amounts of fresh snow each year but remain traversible all year round. Low temperatures are prevalent throughout these western regions, where bleak desolation is unrelieved by any vegetation bigger than a low bush, and where wind sweeps unchecked across vast expanses of arid plain. The Indian monsoon exerts some influence on eastern Tibet. Northern Tibet is subject to high temperatures in the summer and intense cold in the winter.
Document 11: Greece: After a period of confusion following Alexander's death, the Antigonid dynasty, descended from one of Alexander's generals, established its control over Macedon and most of the Greek city-states by 276 BC. From about 200 BC the Roman Republic became increasingly involved in Greek affairs and engaged in a series of wars with Macedon. Macedon's defeat at the Battle of Pydna in 168 BC signalled the end of Antigonid power in Greece. In 146 BC Macedonia was annexed as a province by Rome, and the rest of Greece became a Roman protectorate.
Document 12: Richmond, Virginia: Precipitation is rather uniformly distributed throughout the year. However, dry periods lasting several weeks do occur, especially in autumn when long periods of pleasant, mild weather are most common. There is considerable variability in total monthly amounts from year to year so that no one month can be depended upon to be normal. Snow has been recorded during seven of the twelve months. Falls of 3 inches (7.6 cm) or more within 24 hours occur an average once per year. Annual snowfall, however, is usually light, averaging 10.5 inches (27 cm) per season. Snow typically remains on the ground only one or two days at a time, but remained for 16 days in 2010 (January 30 to February 14). Ice storms (freezing rain or glaze) are not uncommon, but they are seldom severe enough to do any considerable damage.
Document 13: Sohag: Köppen - Geiger climate classification system classifies its climate as hot desert (BWh). Luxor, Minya, Sohag, Qena and Asyut have the widest difference of temperatures between days and nights of any city in Egypt, with almost 16 ° C (29 ° F) difference. Sohag is one of the warmest places in Egypt due to its place in the east side of Sahara in North Africa. Sohag is ranked the 5th driest place in Egypt and the 9th globally. Also ranked 4th warmest place in Egypt and 296th globally.
Document 14: British Isles: Anglo-Saxons arrived as Roman power waned in the 5th century AD. Initially, their arrival seems to have been at the invitation of the Britons as mercenaries to repulse incursions by the Hiberni and Picts. In time, Anglo-Saxon demands on the British became so great that they came to culturally dominate the bulk of southern Great Britain, though recent genetic evidence suggests Britons still formed the bulk of the population. This dominance creating what is now England and leaving culturally British enclaves only in the north of what is now England, in Cornwall and what is now known as Wales. Ireland had been unaffected by the Romans except, significantly, having been Christianised, traditionally by the Romano-Briton, Saint Patrick. As Europe, including Britain, descended into turmoil following the collapse of Roman civilisation, an era known as the Dark Ages, Ireland entered a golden age and responded with missions (first to Great Britain and then to the continent), the founding of monasteries and universities. These were later joined by Anglo-Saxon missions of a similar nature.
Document 15: Egypt: Most of Egypt's rain falls in the winter months. South of Cairo, rainfall averages only around 2 to 5 mm (0.1 to 0.2 in) per year and at intervals of many years. On a very thin strip of the northern coast the rainfall can be as high as 410 mm (16.1 in), mostly between October and March. Snow falls on Sinai's mountains and some of the north coastal cities such as Damietta, Baltim, Sidi Barrany, etc. and rarely in Alexandria. A very small amount of snow fell on Cairo on 13 December 2013, the first time Cairo received snowfall in many decades. Frost is also known in mid-Sinai and mid-Egypt. Egypt is the driest and the sunniest country in the world, and most of its land surface is desert.
ground_truth: Celtic dialects of the Insular Celtic group
sub_queries: What is the sunniest county in the world? Answer: Egypt
in the 1st century bc Egypt became a colony of Answer: the Roman Empire
The people that lived in the British Isles during the the Roman Empire era spoke which language? Answer: Celtic dialects of the Insular Celtic group