The Pyu complete their commercial center of Sri Ksetra in the dry zone of present northern Burma in 638.

Sri Ksetra or Thaye Khittaya (lit., "Field of Fortune" or "Field of Glory"), located eight kilometers southeast of Prome (Pyay) at present-day Hmawza village, is the last and southernmost Pyu capital.

The city, founded between the fifth and seventh centuries, likely overtook Halin as the premier Pyu city by the seventh or eighth century, and will retain that status until the Mranma arrive in the ninth century.

The city is home to at least two dynasties, and maybe three.

The first dynasty, called the Vikrama Dynasty, is believed to have launched the Pyu calendar, which will later become the Burmese calendar, on March 22, 638.

Phraya Kalavarnadit, the legendary first king of Lavo, is said to have established the city of Lavo around 450 CE as one of the Dvaravati city-states.

Kalavarnadit establishes a new era called the Chulasakaraj, which is the era used by the Siamese and the Burmese until the nineteenth century.

Isanavarman I of Chenla expands Khmer influence to the Chao Phraya valley through his campaigns around the seventh century.

Dvaravati cities that fall under Khmer hegemony become Lavo, while the Western cities are spared from Khmer hegemony and form the Kingdom of Supannabhum.

Lavo is the center from which Khmer authority rules over Dvaravatians.

The only native language found during early Lavo times is the Mon language.

However, there is debate whether Mon was the sole ethnicity of Lavo.

Nonetheless, it also should be noted that the area also home to a sizable Malays and Khmer people earlier during Dvaravati period.

Some historians point out that Lavo was composed of mixed Mon and Lawa people (a Palaungic people), with the Mons forming the ruling class.

It is also hypothesized that the migration of Tai people into Chao Phraya valley occurred during the time of the Lavo kingdom.

The transition from the Sui to the Tang dynasty ends in 628, when Emperor Gaozu's son Emperor Taizong of Tang (Li Shimin) destroys the Liang state ruled by the agrarian rebel ruler Liang Shidu and reunifies China.

Taizong, the second emperor of the Tang Dynasty, had encouraged his father, Li Yuan (later Emperor Gaozu) to rise against Sui Dynasty rule at Taiyuan in 617 and subsequently defeated several of his most important rivals.

He immediately faces a crisis, as the Eastern Gökturk Khaganate launches a major incursion toward Chang'an, and just nineteen days after Emperor Taizong takes the throne in 626, the two khans meet across the river and personally negotiate peace terms, including Tang tributes to the Gökturks.

After Taizong subjugates the Xianbei state Tuyuhun in 635, Tuyuhun's southwestern neighbor, the Tibetan state Tufan, rises in power and soon displaces Tuyuhun as the major threat to Tang's west.

Tufan attacks Tuyuhun and Tang in 638 with a grand force of two hundred thousand and while Tang's fifty thousand troops repel the Tufan attack, Emperor Taizong offers a marriage alliance.

For the rest of Emperor Taizong's reign, there will be no further major battles between Tang and Tufan, although Tufan will pose major military threats for almost the rest of Tang Dynasty rule.

Xuanzang, a Chinese Buddhist monk, scholar, traveler, and translator, becomes famous for his seventeen-year overland journey to India.

The Bulgar tribes consolidate under Khan Kurt, or Kubrat, after the defeat of the Avars by Heraclius.

The Bulgars, a Turkic people who are first mentioned in the sources toward the end of the fifth century CE, live at this time in the steppes to the north of the Black Sea.

The Bulgar tribes are composed of skilled, warlike horsemen governed by khans (chiefs) and boyars (nobles).

The Avars had subdued the Bulgars in the sixth century.

Kubrat (also Kurt or Houvrat) is of the kingly Dulo clan, with the authority of the Western Turkic Khaganate, and the rightful heir of the Bulgar throne.

He had spent his adolescence in Constantinople, where he was educated and baptized, while his maternal uncle Organa ruled over his tribe.

Kubrat returns to his fatherland around 628 to become khagan over the Crimean Huns with the support of the Onogur, who have always violently opposed the European Avar Khaganate.

Khan Kubrat manages to unite the two main Bulgar tribes of Kutrigur and Utigur under a single rule between 630 and 635, creating a powerful confederation which is referred to by the medieval authors as The Old Great Bulgaria and also known as The Onogundur-Bulgar Empire.

Some scholars assume that it also included among its subjects a significant portion of the defeated Avars and stretched as far west as the Pannonian plain.

It is presumed that Kubrat’s capital was the ancient city of Phanagoria on the Taman peninsula.

The Khazars, members of a confederation of Turkic-speaking tribes, are in contact with the Persians in the early seventh century. (The origin of the term Khazar and the early history of the Khazar people are obscure, but it is likely that the Khazars were originally located in the northern Caucasus region and were part of the western Turkic empire in present Turkestan).

The tribes constituting the Khazar union are, according to the most widely approved view, basically Turkic groups, such as the Oğuric peoples, including Šarağurs, Oğurs, Onoğurs, and Bulğars, who formed part of the Tiĕlè confederation.

These tribes, many driven out of their homelands by the Sabirs, who in turn fled the Asian Avars, had begun to flow into the Volga-Caspian-Pontic zone from as early as the fourth century CE and are recorded by Priscus to reside in the Western Eurasian steppelands as early as 463.

They appear to stem from Mongolia and South Siberia in the aftermath of the fall of the Hunnic/Xiōngnú nomadic polities.

A variegated tribal federation led by these Tűrks, probably comprising a complex assortment of Iranian, proto-Mongolic, Uralic, and Paleo-Siberian clans, had vanquished the Rouran Khaganate of the hegemonic central Asian Avars in 552 and swept westwards, taking in their train other steppe nomads and peoples from the Sogdian kingdom.

The Khazars have by about 630 become independent of the Turkic empire to the east.

The West Slavs form a polity under Frankish merchant Samo.

A war between the Avars and their west Slav clients, the Wends, is documented by the East Romans and Franks.

In the 630s, Samo, the ruler of the first historically known Slavic polity, Samo's Tribal Union (or Samo's realm), increases his authority over lands to the north and west of the khanate, at the expense of the Avars.

Following this defeat, the prestige and power of the Avars declines.

Both the Persian and East Roman empires have already demobilized, their human and material resources exhausted, and both have ceased to support those client states on the frontiers of the Arabian Peninsula that had restrained the Bedouin of the desert for the past century.

Consequently, they are vulnerable to the sudden emergence of the Islamic Rashidun Caliphate, whose forces invade both empires only a few years after the war.

The Muslim Arabs have overrun Mesopotamia and brought much of central Persia under their control by the end of 639.

Most of the lands of the Persian Empire, including Bactria, the Caucasus, and Makran, are annexed to the Rashidun Caliphate, the first Islamic state.

The Caliphate now begins the conquest of Egypt.