Pre-Columbian era
The earliest known civilization is the Olmec. This civilization established the cultural blueprint by which all succeeding indigenous civilizations would follow in Mexico. Pre-Olmec civilization began with the production of pottery in abundance, around 2300 BCE in the Grijalva River delta. Between 1600 and 1500 BCE, the Olmec civilization had begun, with the consolidation of power at their capital, a site today known as San Lorenzo Tenochtitlán near the coast in southeast Veracruz. The Olmec influence extended across Mexico, into Central America, and along the Gulf of Mexico. They transformed many peoples' thinking toward a new way of government, pyramid-temples, writing, astronomy, art, mathematics, economics, and religion. Their achievements paved the way for the Maya civilization and the civilizations in central Mexico.
Iraqis
In ancient and medieval times Mesopotamia was the political and cultural centre of many great empires, such as the Akkadian Empire, Assyria, and Babylonia. The ancient Mesopotamian civilization of Sumer is the oldest known civilization in the world, and thus Iraq is widely known as the cradle of civilization. Iraq remained an important centre of civilization for millennia, up until the Abbasid Caliphate (of which Baghdad was the capital), which was the most advanced empire of the medieval world (see Islamic Golden Age).