Indus Valley Civilization in the context of "4.2 kiloyear event"

Mesoamerica is a historical region and cultural area comprising the present day lands of central and southern Mexico, all of Belize, Guatemala, El Salvador, western Honduras, and the Greater Nicoya region of Nicaragua and Costa Rica. As a cultural area, Mesoamerica is defined by a mosaic of cultural traits developed and shared by its indigenous cultures.

In the pre-Columbian era, many indigenous societies flourished in Mesoamerica for more than 3,000 years before the Spanish colonization of the Americas began on Hispaniola in 1493. In world history, Mesoamerica was the site of two historical transformations: (i) primary urban generation, and (ii) the formation of New World cultures from the mixtures of the indigenous Mesoamerican peoples with the European, African, and Asian peoples who were introduced by the Spanish colonization of the Americas. Mesoamerica is one of the six areas in the world where ancient civilization arose independently (see cradle of civilization), and the second in the Americas, alongside the Caral–Supe in present-day Peru. Mesoamerica is also one of only five regions of the world where writing is known to have independently developed (the others being ancient Egypt, India, Sumer, and China).

The history of Pakistan preceding the country's independence in 1947 is shared with that of Afghanistan, India, and Iran. Spanning the western expanse of the Indian subcontinent and the eastern borderlands of the Iranian plateau, the region of present-day Pakistan served both as the fertile ground of a major civilization and as the gateway of South Asia to Central Asia and the Near East.

Situated on the first coastal migration route of Homo sapiens out of Africa, the region was inhabited early by modern humans. The 9,000-year history of village life in South Asia traces back to the Neolithic (7000–4300 BCE) site of Mehrgarh in Pakistan, and the 5,000-year history of urban life in South Asia to the various sites of the Indus Valley Civilization, including Mohenjo Daro and Harappa.

The history of navigation, or the history of seafaring, is the art of directing vessels upon the open sea through the establishment of its position and course by means of traditional practice, geometry, astronomy, or special instruments. Many peoples have excelled as seafarers, prominent among them the Austronesians (Islander Southeast Asians, Malagasy, Islander Melanesians, Micronesians, and Polynesians), the Harappans, the Phoenicians, the Iranians, the ancient Greeks, the Romans, the Arabs, the ancient Indians, the Norse, the Chinese, the Venetians, the Genoese, the Hanseatic Germans, the Portuguese, the Spanish, the English, the French, the Dutch, and the Danes.

A fortification (also called a fort, fortress, fastness, or stronghold) is a military construction designed for the defense of territories in warfare, and is used to establish rule in a region during peacetime. The term is derived from Latin fortis ("strong") and facere ("to make").

From very early history to modern times, defensive walls have often been necessary for cities to survive in an ever-changing world of invasion and conquest. Some settlements in the Indus Valley Civilization were the first small cities to be fortified. In ancient Greece, large cyclopean stone walls fitted without mortar had been built in Mycenaean Greece, such as the ancient site of Mycenae. A Greek phrourion was a fortified collection of buildings used as a military garrison, and is the equivalent of the Roman castellum or fortress. These constructions mainly served the purpose of a watch tower, to guard certain roads, passes, and borders. Though smaller than a real fortress, they acted as a border guard rather than a real strongpoint to watch and maintain the border.

The 3rd millennium BC spanned the years 3000 to 2001 BC. This period of time corresponds to the Early to Middle Bronze Age, characterized by the early empires in the Ancient Near East. In Ancient Egypt, the Early Dynastic Period is followed by the Old Kingdom. In Mesopotamia, the Early Dynastic Period is followed by the Akkadian Empire. In what is now Northwest India and Pakistan, the Indus Valley Civilization developed a state society.

World population growth relaxed after the burst due to the Neolithic Revolution.World population was largely stable, at roughly 60 million, with a slow overall growth rate at roughly 0.03% p.a.