There is much confusion over the chronology of the early Gupta kings as well as over the beginning of the Gupta Era. After much discussion, Goyal has shown that the king Gupta ruled from c. AD 295 to c. AD 300 and his son Ghatotkacha from c. AD 300 to c. AD 319. Chandragupta I ascended the throne in AD 319 or 320 and ruled till AD 350.
Goyal believes that the Gupta era commenced either on February 26, AD 320 or on December 20, AD 318. Goyal also believes that the event from which the era was reckoned was neither the accession of Samudragupta nor the marriage of Chandragupta I with Kumaradevi as suggested by many, scholars the first known date of the Gupta era is the year 56, the date of the accession of Chandragupta II it seems Chandragupta II reckoned it probably from the date of accession of Chandragupta I, the first maharajadhiraja of the dynasty or from the date of the assumption of the imperial status by the latter. May be, both these events took place simultaneously.
Capital of the Guptas
Generally speaking two factors determined the location of the capitals of the north Indian empires. Firstly, the region from which they derived their strength and secondly, the directions from which they perceived threats by internal and external dangers. Pataliputra, Purushapura, Thanesar, Kanauj, and Delhi, all the capitals at different periods, confirm this.
It has already been shown that in the post-Kushana period the centre of the political gravity had shifted to the eastern part of the upper Ganga basin. It was in the eastern UP as his political base that Samudragupta launched his campaigns. Hence, one would expect that the capital of the Guptas was located somewhere in the eastern part of UP.
The evidence of the Pur anas from which we know that Prayaga was the nucleus of the early Gupta states, the incisions of the prashasti of Samudragupta on a pillar at Prayaga, the discovery of several other early Gupta inscriptions and numerous hoards of coins from this area and the possibility of the performance of ashvamedha (chitrotsanna) at Prayaga by Samudragupta bring out the fact that at least in the early part of their history, the Guptas had their capital at Prayaga.
Later on, however, Ayodhya was made the formal residence of the emperor, for Paramartha, a Buddhist scholar of the Gupta age refers to this city as the capital of Vikramaditya i.e. Skandagupta who appointed Vasubandhu as the teacher of his crown-prince Baladitya. It is quite possible that Ayodhya was accorded this status by Paramabhagavata Chandragupta II or his father.
It is, however, almost universally believed that Pataliputra was the chief metropolis of the Gupta Empire. According to Goyal, it appears to be a byproduct of the equally erroneous view that Magadha was the original home of the imperial Guptas. R.K. Mookerji pointed out that the description of Pataliputra as given by Fa-hien who visited it during the reign of Chandragupta II, gives the impression that Pataliputra did not occupy the same position of importance in the Gupta Empire that it had in the Mauryan Empire.