While a few fragments exist, there is no surviving historical work which dates to the hundred years following Alexander's death. The works of the major Hellenistic historians Hieronymus of Cardia (who worked under Alexander, Antigonus I and other successors), Duris of Samos and Phylarchus which were used by surviving sources are all lost. The earliest and most credible surviving source for the Hellenistic period is Polybius of Megalopolis (c. 200-118), a statesman of the Achaean League until 168 BCE when he was forced to go to Rome as a hostage. His Histories eventually grew to a length of forty books, covering the years 220 to 167 BCE.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What is the earliest, most credible source of the Hellenistic period?
Ah, so.. Polybius

By far the largest military action in which the United States engaged during this era was the War of 1812. With Britain locked in a major war with Napoleon's France, its policy was to block American shipments to France. The United States sought to remain neutral while pursuing overseas trade. Britain cut the trade and impressed seamen on American ships into the Royal Navy, despite intense protests. Britain supported an Indian insurrection in the American Midwest, with the goal of creating an Indian state there that would block American expansion. The United States finally declared war on the United Kingdom in 1812, the first time the U.S. had officially declared war. Not hopeful of defeating the Royal Navy, the U.S. attacked the British Empire by invading British Canada, hoping to use captured territory as a bargaining chip. The invasion of Canada was a debacle, though concurrent wars with Native Americans on the western front (Tecumseh's War and the Creek War) were more successful. After defeating Napoleon in 1814, Britain sent large veteran armies to invade New York, raid Washington and capture the key control of the Mississippi River at New Orleans. The New York invasion was a fiasco after the much larger British army retreated to Canada. The raiders succeeded in the burning of Washington on 25 August 1814, but were repulsed in their Chesapeake Bay Campaign at the Battle of Baltimore and the British commander killed. The major invasion in Louisiana was stopped by a one-sided military battle that killed the top three British generals and thousands of soldiers. The winners were the commanding general of the Battle of New Orleans, Major General Andrew Jackson, who became president and the Americans who basked in a victory over a much more powerful nation. The peace treaty proved successful, and the U.S. and Britain never again went to war. The losers were the Indians, who never gained the independent territory in the Midwest promised by Britain.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"):  What country was the first the UK ever declared war upon?
Ah, so.. unanswerable

The early Christian philosophy of Augustine of Hippo was heavily influenced by Plato. A key change brought about by Christian thought was the moderatation of the Stoicism and theory of justice of the Roman world, as well emphasis on the role of the state in applying mercy as a moral example. Augustine also preached that one was not a member of his or her city, but was either a citizen of the City of God (Civitas Dei) or the City of Man (Civitas Terrena). Augustine's City of God is an influential work of this period that attacked the thesis, held by many Christian Romans, that the Christian view could be realized on Earth.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What is one thing that Plato changed in the Roman world?
Ah, so..
unanswerable