Kālidāsa
The most popular theory is that Kalidasa flourished during the reign of Chandragupta II, and therefore lived around 4th-5th century CE. Several Western scholars have supported this theory, since the days of William Jones and A. B. Keith. Many Indian scholars, such as Vasudev Vishnu Mirashi and Ram Gupta, also place Kalidasa in this period. According to this theory, his career might have extended to the reign of Kumaragupta I (r. 414 – 455 CE), and possibly, to that of Skandagupta (r. 455 – 467 CE).
Vikramaditya
There were 18 kingdoms in Vikramaditya's empire of "Bharatavarsha" (India). After a flawless reign, he ascended to heaven. At the beginning of the Kali Yuga, Vikramaditya came from Kailasa and convened an assembly of sages from the Naimisha Forest. Gorakhnath, Bhartrhari, Lomaharsana, Saunaka and other sages recited the Puranas and the Upapuranas. A hundred years after Vikramaditya's death, the Shakas invaded India again. Shalivahana, Vikramaditya's grandson, subjugated them and other invaders. Five hundred years after Shalivahana's death, Bhoja defeated later invaders.