415 (POD)- Chandragupta II (or Chandragupta Vikramaditiya) doesn't die like he did in OTL.
416- Chandragupta II directs a campaign for the Himalayas and Tibet, and another for the entire Indian Subcontinent
418- By this time, the Himalayas are under control of the Gupta Empire, and so are the Yaudhaya, Arjunaya, and Western Satraps.
420- The Gupta Empire has conquered the Vakatakas, Daksina, Nala, Kottura, Rashtrakutas, Kadambas, Gangas, and Pallavas
425- All of the Indian subcontinent is under Gupta control (including Sri Lanka)
426- Southern Tibet is under Gupta control
430- Chandragupta II dies, Kumaragupta I succeeds him
431- Kumaragupta announces that he will continue his late father's campaign, and sets up a network of spies, diplomats, and informers
449- The Gupta Empire is told by the network of spies and informers that the Hunas were planning an attack, and thus set up a complex towards their north-western border, a tradition that would follow through to the many attacks of the Hunas, and other invaders from that area.
452- Kumaragupta has defeated the Hunas, but they flee before they can be captured
453- Kumaragupta dies, Skandagupta succeeds him
455- Skandagupta repels a Huna attack
460- All of Tibet is under Gupta control, Gupta Empire is now invading Liu Song China
462- Due to the extensive military turmoil of Liu Song China, at least 1/10 of it falls to the Guptas
464- A sort of a small "neutral zone" is created in Liu Song China between the Gupta Empire and southern China.
467- Skandagupta dies, Narasimhagupta succeeds him
472- The "neutral zone" is conquered by the Gupta Empire
475- Due to military instability in Liu Song China, much of it secedes from Liu Song China and joins the Gupta Empire
476- The great mathematician and astronomer Aryabhatta is born
477- Narasimhagupta receives news of the fall of the Western Roman Empire
478- After extensive resistance, Liu Song China surrenders all lands, and government to the Gupta Empire
479- The Gupta Empire starts invading Northern Wei China on a small-scale. Also: Narasimhagupta starts a policy of cultural tolerance in an effort to unite his people, encouraging translating documents into the languages of his colonies, as well as encouraging citizens to move from "Gupta proper" to his "colonies" and take spouses with those who had already lived there, in order to make it all "Gupta proper". He also grants full citizenship to all adults in his empire. This would help him later as it would unite the people under the Empire, and leave a cultural legacy