The Deutero-Malays, an Iron Age or Bronze Age people descended partly from the Chams of Cambodia and Vietnam, push the Proto-Malays inland around 300 BCE.

The first group in the peninsula to use metal tools, the Deutero-Malays are the direct ancestors of today's Malaysian Malays, and bring with them advanced farming techniques.

The Malays share a common culture and social structure but remain politically fragmented throughout the Malay archipelago.

The culture of Japan’s Yayoi people, whose comparatively large settlements are centered in southwestern and central Japan, displays a marked change in orientation from the Jomon culture it succeed circa 300 BCE.

Wet-rice cultivation and bronze technology are apparently introduced from Korea by way of Kyushu.

Yayoi ceramics , in contrast to the robust Jomon wares, are made with finer clay, are turned on a wheel, are generally more utilitarian in character, and feature more casual, occasionally elegant, decoration.

Alexander’s conquests and the subsequent partition of Alexander's empire into four major states with Macedonian dynasts has greatly facilitated communication from India to Sicily, as the Greek language spreads and becomes the lingua franca for culture, commerce, and administration throughout the Near East.

The Middle East: 309–298 BCE

Linguistic and Cultural Shifts and the Babylonian War

The Babylonian War and the Rise of Seleucus

The Babylonian War (311–309 BCE) between Diadochi kings Antigonus I Monophthalmus and Seleucus I Nicator ends in a decisive victory for Seleucus. This conflict eliminates any chance of restoring Alexander's empire, a reality confirmed at the subsequent Battle of Ipsus. The outcome solidifies Seleucus's control over the eastern satrapies, marking the emergence of the extensive Seleucid Empire.

Evolution of the Old Persian Language

During the late fourth century BCE, the Old Persian language, known through inscriptions, clay tablets, and seals, transitions significantly. Inscriptions from the reigns of Artaxerxes II and Artaxerxes III evolve into a form of "pre-Middle Persian," setting the stage for Middle Persian and eventually New Persian, the foundation of modern Persian dialects. Recent discoveries in the Persepolis Fortification Archive at the Oriental Institute reveal practical administrative texts in Old Persian, highlighting broader use beyond royal ceremonial contexts.

The Babylonian War, a conflict fought from 311 BCE to 309 BCE between the Diadochi kings Antigonus I Monophthalmus and Seleucus I Nicator, ends in a victory for the latter.

The conflict ends any possibility of restoration of the empire of Alexander the Great, a result confirmed in the Battle of Ipsus.

It also marks the infancy of the Seleucid Empire by giving Seleucus control over the eastern satrapies of Alexander's former empire.

The Old Persian language, one of the two directly attested Old Iranian languages (the other being Avestan, the language of Zoroastrian religious tradition), appears primarily in the inscriptions, clay tablets, and seals of the Achaemenid era (about 600 BCE to 300 BCE).

Examples of Old Persian have been found in what is now present-day Iran, Iraq, Turkey and Egypt, the most important attestation by far being the contents of the Behistun Inscription (dated to 525 BCE).

Recent research into the vast Persepolis Fortification Archive at the Oriental Institute at the University of Chicago have unearthed Old Persian tablets (2007).

This new text shows that the Old Persian language was a written language in use for practical recording and not only for royal display.

By the fourth century, the late Achaemenid period, the inscriptions of Artaxerxes II and Artaxerxes III differ enough from the language of Darius' inscriptions to be called a "pre-Middle Persian," or "post-Old Persian."

Old Persian now begins to evolve into Middle Persian, which is in turn the genetic ancestor of New Persian.

Chandragupta Maurya leads a series of campaigns in the Indus Valley in 305 BCE to retake the satrapies left behind by Alexander the Great when he returned westwards.

Seleucus I Nicator fights to defend these territories, but both sides make peace in 303 BCE.

The treaty ends the Seleucid–Mauryan war and allows Chandragupta control of the regions over which he has gone to war.

Near East (309–298 BCE): Euclid and the Foundations of Geometry

In the intellectual milieu of the Hellenistic Near East, the renowned mathematician Euclid, active in Alexandria around 300 BCE, fundamentally shapes the future of mathematics and science. He formulates a systematic set of axioms for geometry, laying the groundwork for a coherent, logical structure that will become known as Euclidean geometry. His influential text, the Elements, meticulously compiles these axioms and proofs, profoundly influencing the direction of mathematical thought.

Euclid’s scientific contributions extend beyond pure mathematics. In his works Optics and Catoptrics, he articulates the correct law of reflection, applying it rigorously to both plane and curved mirrors. He further references the phenomenon of refraction, demonstrating a sophisticated understanding of optical principles that will inform subsequent scientific inquiry in the Hellenistic world and beyond. Euclid’s work thus embodies the broader intellectual dynamism and methodological rigor characterizing the scholarly pursuits flourishing under the patronage of Hellenistic Alexandria.

Euclid, working in Hellenistic Alexandria in about 300 BCE, establishes a set of axioms for geometry.

Around the same time, he writes a treatise entitled Optics and Catoptrics, in which he sets forth the correct law of reflection and applies the law to the study of plane and curved mirrors.

He also mentions the phenomenon of refraction.

The End of the Iron Age Cold Epoch and the Onset of the Subatlantic Period (c. 300 BCE)

Around 300 BCE, the Iron Age Cold Epoch came to an end, marking a significant climatic shift in Western Europe. This transition ushered in the Subatlantic Period, characterized by milder winters and relatively warm summers, creating more stable environmental conditions for human populations.

Climatic Changes and Their Impact

• Warmer and more temperate conditions replaced the cooler and harsher climate of the preceding Iron Age Cold Epoch.
• Increased precipitation likely supported the expansion of woodlands and agricultural productivity.
• The return to a stable, favorable climate contributed to population growth, economic expansion, and urbanization across many Iron Age societies.

Effects on Western European Cultures

• Celtic La Tène Expansion – The improved climate coincided with the peak of La Tène culture (c. 450 BCE–1st century BCE), which saw the expansion of Celtic societies across Gaul, Britain, Iberia, and Central Europe.
• Advancements in Agriculture – The milder climate supported intensified farming and the expansion of settlements and trade networks.
• Increased Contact with the Mediterranean – Improved conditions facilitated long-distance trade, as Celtic tribes and Mediterranean civilizations (Greeks, Carthaginians, and Romans) exchanged goods, technologies, and cultural influences.

Significance of the Subatlantic Period

• This climate stability persisted for centuries, influencing Roman-era agriculture, trade, and settlement patterns.
• The end of the Iron Age Cold Epoch played a role in shaping the social and economic landscape of Europe, paving the way for larger, more complex societies.
• The milder climate of the Subatlantic Period would remain dominant until later medieval climate fluctuations, such as the Roman Warm Period and the Little Ice Age.

Thus, by 300 BCE, the transition from the Iron Age Cold Epoch to the Subatlantic Period contributed to the expansion and development of Iron Age European societies, reinforcing the conditions that would shape early state formations and the rise of powerful civilizations.