During the Achaemenid Persian Empire, around 600 BC the Persians first began to use the abacus.

During the first invasion, Thrace, Macedon and the Aegean Islands were added to the Persian Empire, and Eretria was duly destroyed.

During this period, Athens and Sparta rose to a position of political eminence in Greece, and their rivalry in the aftermath of the Persian wars brought Greece into renewed internal conflict.

During this time, Jews have experienced slavery, anarchic and theocratic self-government, conquest, occupation, and exile ; in the Diasporas, they have been in contact with and have been influenced by ancient Egyptian, Babylonian, Persian, and Hellenic cultures, as well as modern movements such as the Enlightenment ( see Haskalah ) and the rise of nationalism, which would bear fruit in the form of a Jewish state in the Levant.

During the second Persian invasion of Greece ( 480-479 BC ) Megara fought alongside the Spartans and Athenians at crucial battles such as Salamis and Plataea.

During the war between the Scythians and the Persian Empire, the Scythians came to dominate the Neuri.

During the years 550 to 330 BC, coinciding with the sovereignty of the first Persian Empire over the Middle East area, especially the whole part of the Persian Gulf and some parts of the Arabian Peninsula, the name of " Pars Sea " is widely found in the compiled written texts.

During the end of the fourth millennium BC, the southern part of the Persian Gulf was dominated by the Dilmun civilization.

During the 7th century the Sassanid Persian empire conquered the whole of the Persian Gulf, including southern and northern shores.

During his reign the Roman eastern frontier underwent extensive re-fortification, including the construction of Dara, a stronghold intended to counter the Persian fortress of Nisibis.

During their rule they extensively invited, and received, a steady stream of Persian scholars, poets, jurists, architects, and painters.

During this time he published Histoire de Nader Chah ( 1770 ), a French translation of a work originally written in Persian by Mirza Mehdi Khan Astarabadi.

During his studies, he dedicated himself to mastering English — adding this language to the Persian, Turkish, Arabic and French, languages in which he was already fluent-so that he could translate the letters of ` Abdu ' l-Bahá and serve as his secretary.

During the Achaemenid period, Sogdiana and Bactria were part of the Persian empire.

During the first Persian invasion of Greece, he fought at the Battle of Marathon, and was possibly one of the 10 Athenian strategoi ( generals ) in that battle.

During the nineteenth and early twentieth centuries, the pearling industry thrived in the relative calm at sea, providing both income and employment to the people of the Persian Gulf.

During the Middle Ages, heliocentric models may have also been proposed by the Indian astronomer, Aryabhata, and by the Persian astronomers, Albumasar and Al-Sijzi.

* Middle East: During the Persian empire, Zoroaster, aka Zarathustra, founded Zoroastrianism, a dualistic philosophy.

* During the turmoil of the An Shi Rebellion, the Chinese seaport Guangzhou is sacked by Arab and Persian raiders.

During the closing stages of the Iran-Iraq War the United States Navy began conducting operations in the Persian Gulf to protect US-flagged ships from attack by Iranian naval forces.

During the Persian invasion of 480 BC it manned the second largest Greek fleet ( 60 ships ), but took no active part in the war.

During this period the Muslim world was a cauldron of cultures which collected, synthesized and significantly advanced the knowledge gained from the ancient Roman, Chinese, Indian, Persian, Egyptian, North African, Greek and Byzantine civilizations.

During the Gulf War, the HARM was involved in a friendly fire incident when the pilot of an F-4G Wild Weasel escorting a B-52 bomber mistook the latter's tail gun radar for an Iraqi AAA site.

During the Gulf War, if an aircraft was illuminated by enemy radar a bogus " Magnum " call on the radio was often enough to convince the operators to power down.

During the first Gulf War the United Nations activated a biological and chemical response team, Task Force Scorpio, to respond to any potential use of weapons of mass destruction on civilians.

During the sixth and final colonial war, the French and Indian War, the military conflicts in Nova Scotia included: Battle of Fort Beauséjour ; Bay of Fundy Campaign ( 1755 ); the Battle of Petitcodiac ; the Raid on Lunenburg ( 1756 ); the Louisbourg Expedition ( 1757 ); Battle of Bloody Creek ( 1757 ); Siege of Louisbourg ( 1758 ), Petitcodiac River Campaign, Gulf of St. Lawrence Campaign ( 1758 ), St. John River Campaign, and Battle of Restigouche.

During the same period, vessels targeting right and bowhead whales in the Gulf of Alaska, Sea of Okhotsk, and the Western Arctic would take the odd gray whale if neither of the more desirable two species were in sight.

During this voyage Alarcón proved to his satisfaction that no open-water passage existed between the Gulf of California and the South Sea.

During the 1980s a captured Sandinista commando revealed that Montoneros " Special Forces " were training Sandinista frogmen and conducting gun runs across the Gulf of Fonseca to the Sandinista allies in El Salvador, FMLN guerrillas.

During the Ice Ages, the sea level of the Atlantic Ocean dropped so much that the Baltic Sea, the Gulf of Bothnia, and the Gulf of Finland disappeared, and the countries now surrounding them, including Germany, Poland, the other Baltic countries and Scandinavia, were directly joined by land.

During the winter or dry season, extending roughly from November to April, the monsoon winds usually blow from the northeast along the China coast and across the Gulf of Tonkin, picking up considerable moisture ; consequently the winter season in most parts of the country is dry only by comparison with the rainy or summer season.

During the Gulf War of 1991, Sepecat Jaguar GR1A bombers of the Royal Air Force featured such Viz characters as Johnny Fartpants, the Fat Slags and Buster Gonad as nose art.

During this time, the definition of Epirus came to encompass the entire coastal region from the Ambracian Gulf to Dyrrachium ( modern-day Durrës, in Albania ).

During the first Gulf War the United Nations activated a biological and chemical response team, Task Force Scorpio, to respond to any potential use of weapons of mass destruction on civilians.

During the Second World War, the Battle of the St. Lawrence involved a number of submarine and anti-submarine actions throughout the lower St. Lawrence River and the entire Gulf of Saint Lawrence, Strait of Belle Isle and Cabot Strait from May to October 1942, September 1943, and again in October and November 1944.

During several expeditions, they discovered two major fault lines, one lying north-south, the Kerna fault, and the other lying east-west, the Delphic fault, which parallels the shore of the Corinthian Gulf.

During his charting of the Gulf Coast in 1785, the Spanish explorer José de Evia named the island Gálvez-town or Gálveztown in honor of Bernardo de Gálvez y Madrid, Count of Gálvez.

During the Gulf War, coalition forces displayed single chevrons on their armoured vehicles to prevent friendly fire incidents.

During this time the Persian empire extends as far west as Macedonia and Libya and as far east as the Hyphasis ( Beas ) River ; it stretches to the Caucasus Mountains and the Aral Sea in the north and to the Persian Gulf and the Arabian Desert in the south.

During the 1940s and 1950s, general semantics entered the idiom of science fiction, most notably through the works of A. E. van Vogt, The World of Null-A and its sequels, and Robert A. Heinlein, Gulf.

During moments of intense crisis the responsibility of political leaders is overwhelming.

During the years when Israel was passing from crisis to crisis -- the Sinai campaign, the infusion of multitudes of penniless immigrants -- it was felt that the purpose of national unity could be best served if the secular majority were to yield to the religious parties.

During the Financial crisis of 2007 – 2010, Bulgaria marked a decline in its economy of 5. 5 % in 2009, but quickly restored its positive growth to 0. 2 % in 2010, in contrast to other Balkan countries.

During the course of 2009, the grim forecasts for the effects of the global crisis on the Bulgarian economy largely materialized.

During the Savings and Loan crisis, the team and Mr. Bright's Savings and Loan were taken over by the FSLIC.

During the third century crisis ( 235 – 285 ), the government resorted to requisition rather than payment in debased coinage, since it could never be sure of the value of money.

During the secession crisis in Missouri at the beginning of the American Civil War, Atchison sided with Missouri's pro-Confederate governor, Claiborne Jackson.

During the 6 February 1934 crisis, France faced the greatest domestic political turmoil since the Dreyfus Affair when the fascist Francist Movement and multiple far right movements rioted en masse in Paris against the French government resulting in major political violence.

During the Suez crisis, Nehru's right hand man, Menon attempted to persuade a recalcitrant Gamal Nasser to compromise with the West, and was instrumental in moving Western powers towards an awareness that Nasser might prove willing to compromise.

During the abdication crisis of December 1936, Ribbentrop reported to Berlin that the reason the crisis had occurred was an anti-German Jewish-Masonic-reactionary conspiracy to depose Edward ( whom Ribbentrop represented as a staunch friend of Germany ), and that civil war would soon break out in Britain between the King's supporters and those of Prime Minister Stanley Baldwin's.

During the fuel crisis of the 1970s, Saab-Valmet developed and series-produced the Saab 99 Petro that ran on kerosene, turpentine or gasoline.

During the " nullification crisis " of 1828 – 1833, South Carolina passed an Ordinance of Nullification purporting to nullify two federal tariff laws.

During the 2009 Malagasy political crisis, Russia's Foreign Minister Sergey Lavrov stated that Russia is " concerned by the increased frequency of attempts on the African continent to resort to non-constitutional methods of solving internal political problems.

During 1975, two years after the military coup that ended the government of Salvador Allende, the economy of Chile experienced a severe crisis.

During the financial crisis of 2007 – 2010, several Keynesian economists such as James Galbraith and Joseph Stiglitz blamed the free market philosophy of Friedman and the Chicago school for the economic turmoil.

During the crisis Burma deployed thousands of troops on its border with Bangladesh.

* During the 1975 constitutional crisis, on 11 November 1975, the governor-general, Sir John Kerr, dismissed the Labor Party's Gough Whitlam as prime minister.

During the European sovereign-debt crisis, after incurring a € 900 million debt, the people of Parma voted in a direct democratic platform.

During the 2007-2012 global financial crisis in the United States, the neologism " pessimism porn " was coined to describe the alleged eschatological and survivalist thrill some people derive from predicting, reading and fantasizing about the collapse of civil society through the destruction of the world's economic system.

During this crisis, new ideas, perhaps ones previously discarded, are tried.

During the economic reforms being implemented after the financial crisis, the information technology ( IT ) sector was one of several that was targeted and considered to be an important factor in the recovery of the nation ’ s economy.

During World War I, Switzerland suffered an economic crisis.