Persia is Iran it was called Persia until around mid 1900's The Persian Empire was a series of historical empires that ruled over the Iranian plateau, the old Persian homeland, and beyond in Western Asia, Central Asia and the Caucasus. Today the nation of Persia is known primarily as Iran.The most widespread entity considered to have been a Persian Empire was the Achaemenid Empire (550–330 BC) under Darius and Xerxes (or Xerkes) — famous in antiquity as the foe of the classical Greek states (See Greco-Persian Wars) — a united Iranian kingdom that originated in the region now known as Pars province of Iran.It was formed under Cyrus the Great, who overthrew the empire of the Medes, and conquered much of the Middle East, including the territories of the Babylonians (Asuristan), the Phoenicians, and the Lydians. Cyrus' son, Cambyses, continued Cyrus' conquests by conquering Egypt.Most of the successive states in Greater Iran prior to March 1935 are collectively called the Persian The Islamic conquest of Persia (633–656) led to the end of the Sassanid Empire and the eventual decline of the Zoroastrian religion in Persia. However, the achievements of the previous Persian civilizations were not lost, but were to a great extent absorbed by the new Islamic polity.Many historians have long offered the idea that Persia, on the verge of the Arab invasion, was a society in decline and decay and thus it embraced the invading Arab armies with open arms. This view is not widely accepted however. Some authors have for example used mostly Arab sources to illustrate that "contrary to the claims of Muslim apologists, Iranians in fact fought long and hard against the invading Arabs."[1] This view further more holds that once politically conquered, the Persians began engaging in a culture war of resistance and succeeded in forcing their own ways on the victorious Arabs.[2][3]Mesopotamia was a cradle of civilization geographically located between the Tigris and Euphrates rivers, largely corresponding to modern-day Iraq. Sumer in southern Mesopotamia is commonly regarded as the world's earliest civilization. Cities in Mesopotamia later served as capitals of the Akkadian, Babylonian, Assyrian, Mitanni, Neo-Assyrian, Neo-Babylonian, Parthian, Sassanid and Abbasid empires. At other times, the region was ruled by foreign powers, notably the Achaemenid, Seleucid, Rashidun, Umayyad and Ottoman empires and kings.Timeline of Ancient Mesopotamia Overview map of ancient Mesopotamia Archaeological sites of MesopotamiaMesopotamian history extends from the emergence of Urban societies in Southern Iraq in the 4th millennium BC to the arrival of Alexander the Great in the 4th century BC (which is seen as the hallmark of the Hellenization of the Near East, therefore supposedly marking the "end" of Mesopotamia). A cultural continuity and spatial homogeneity for this entire historical geography ("the Great Tradition") is popularly assumed, though the assumption is problematic. Mesopotamia housed some of the world's most ancient states with highly developed social complexity. The region was famous as one of the four riverine civilizations where writing was first invented, along with the Nile valley in Egypt, the Indus Valley in the Indian Subcontinent and Yellow River valley in China (Although writing is also known to have arisen independently in Mesoamerica and the Andes).Mesopotamia housed historically important cities such as Uruk, Nippur, Nineveh, and Babylon as well as major territorial states such as the Akkadian kingdom, Third Dynasty of Ur, and Assyrian empire. Some of the important historical Mesopotamian leaders were Ur-Nammu (king of Ur), Sargon (who established the Akkadian Kingdom), Hammurabi (who established the Old Babylonian state), and Tiglath-Pileser I (who established the Assyrian Empire)."Ancient Mesopotamia" includes the period from the late 4th millennium BC until the rise of the Achaemenid Persians in the 6th century BC. This long period may be divided as follows:Late Neolithic: Hassuna, Samarra and Halaf "cultures" Chalcolithic: Ubaid period (ca 5900 BC–4000 BC) Uruk period (ca 4000 BC–3100 BC) Early Bronze Age Jemdet Nasr Period (ca 3100 BC–2900 BC) Early Dynastic city states (ca 2900 BC–2350 BC) Akkadian Empire (ca 2350 BC–2193 BC). Third dynasty of Ur ("Sumerian Renaissance" or "Neo-Sumerian Period") (ca 2119 BC–2004 BC) Middle Bronze Age Early Assyrian kingdom (20th to 18th c. BC) First Babylonian Dynasty (18th to 17th c. BC) Late Bronze Age Kassite dynasty, Middle Assyrian period (16th to 12th c. BC) Iron Age Syro-Hittite or Neo-Hittite regional states (11th–7th c. BC) Neo-Assyrian Empire (10th to 7th c. BC) Neo-Babylonian Empire (7th to 6th c. BC) Achaemenid Persian Empire (6th-4th c. BC) Dates are approximate for the second and third millennia BC; compare Chronology of the Ancient Near East.Language and writingThe earliest language written in Mesopotamia was Sumerian, a complex language isolate. Scholars agree that other languages were also spoken in early Mesopotamia along with Sumerian. Later a Semitic language, Akkadian, came to be the dominant language, although Sumerian was retained for administration, religious, literary, and scientific purposes. Different varieties of Akkadian were used until the end of the Neo-Babylonian period. Then Aramaic, which had already become common in Mesopotamia, became the official provincial administration language of the Achaemenid Persian Empire. Akkadian fell into disuse, but both it and Sumerian were still used in temples for some centuries.In Early Mesopotamia (around mid 4th millennium BC) cuneiform script was invented. Cuneiform literally means "wedge-shaped", due to the triangular tip of the stylus used for impressing signs on wet clay. The standardized form of each cuneiform sign appear to have been developed from pictograms. The earliest texts (7 archaic tablets) come from the Eanna super sacred precinct dedicated to the goddess Inanna at Uruk, Level III, from a building labeled as Temple C by its excavators.The system of cuneiform script was difficult to master. Thus only a limited number of individuals were hired as scribes to be trained in its reading and writing. It was not until the widespread use of the phonetic Akkadian script was adopted under Sargon's rule that significant portions of Mesopotamian population became learned in literacy. Massive archives of texts were recovered from the archaeological contexts of Old Babylonian scribal schools, through which literacy was disseminated.This is from Wikipeadea but should give you enough information to search on your own