The Indian National Calendar is the Saka calendar, which begins from 78 AD. It was officially adopted in 1957 because independent India wished to have its own calendar and didn’t want to rely solely on the Gregorian calendar, which has European and Christian roots and is seen as a remnant of colonial rule.

India has many calendars; different communities use different calendars in different regions. Therefore, it is very difficult to create a single Indian calendar, even if it follows traditional rules. Buddhists follow the Buddhist calendar, Jains follow the Jain calendar, Sikhs and Muslims have their own calendars.

There are also regional calendars for North India and South India. Neighbouring countries like Nepal use a different calendar known as Vikram Samvat (starting from 57 BC), while India has opted for the Saka calendar.

The question arises: if we use terms like Vikram Samvat (the era said to have begun under king Vikramaditya) or the Saka calendar (which begins with the rule of the Saka kings), what do these names mean and where do they come from? There is much confusion surrounding them. To understand the difference between the Vikram and Saka calendars, we need to delve into history—and even before that, into geography.

Vikram and Saka eras
North India is separated from South India by the Vindhya Mountains. The southern edge of North India was marked by the city of Ujjain, while the northern edge of South India was marked by Pratishthan (or Paithan) in the Godavari Basin. Between them lay the Vindhya Mountains and the Narmada River. Significant trade took place through this region, and kings who controlled it were very powerful, as this was the only land route that gave North India access to South India’s maritime trade routes.

The term Vikram Samvat is believed to be named after king Vikramaditya, who defeated foreign invaders, while the Saka Samvat is linked to a king called Shalivahana, who also repelled foreign Saka or Scythian invasions.

Now, who were these foreign invaders? India has always faced a shortage of horses, which were often imported from Central Asia. Many Central Asian tribes who brought horses ended up ruling and controlling Indian trade routes. The Sakas controlled much of the Aravalli region and came to India around 100 BCE, while the Kushans controlled many of the Gangetic trade routes and arrived around 100 AD.

Myth around three kings: Vikramaditya, Shalivahana, and Bhoja
According to legend, a Jain monk named Kalakacharya was angered by King Gardabhilla of Ujjain, who had abducted his sister, a Jain nun. Kalakacharya sought help from the Saka kings to invade Ujjain, defeat the king, and rescue his sister. The Sakas succeeded, became rulers of Ujjain, and exiled the king. He eventually died in the forest, reportedly eaten by a tiger. His son, Vikramaditya, rose up, defeated the Sakas, expelled them, and established the Vikram Samvat. Or so the legend goes.

There is no historical evidence for this legend, but it remains a part of popular Jain mythology. Many South Indian scholars believe the Saka calendar is named after Shalivahana, who—like Vikramaditya—drove the Sakas out of Pratishthan. Shalivahana belonged to the Satavahana dynasty.

This is first recorded in inscriptions from the 9th century, and it is around this time that stories of Vikramaditya and Shalivahana appear in folk tale collections like the Vikramaditya Pachisi and the Singhasan Battisi. In fact, three kings are commonly mentioned—Vikramaditya, Shalivahana, and Bhoja—all associated with the region between Ujjain and Paithan in central India. According to these tales, Vikramaditya was ultimately killed by Shalivahana, who was said to be a magical child born of a potter’s daughter and the Naga king Vasuki.

When legends eclipse history
In another version, Shalivahana created an army using clay dolls, which was magically aided by the Nagas. In this story, he helps Vikramaditya. In the Bhavishya Purana (composed after 1500 AD), Shalivahana is considered the grandson of Vikramaditya. It also states that Vikramaditya encountered a vision of Jesus Christ, and Shalivahana encountered Muhammad, which is peculiar given that there is approximately a gap of 600 years between Jesus and Muhammad, casting doubt on the plausibility of the claim.

All of this suggests that these are imaginative tales, perhaps composed during the time of Mihir Bhoja, a literary and intellectual king of Ujjain who lived around the 10th century AD. It is said that he discovered the throne of Vikramaditya and regarded himself as its spiritual heir. It is likely he compiled the stories of Shalivahana. Therefore, the legends of Shalivahana, Vikramaditya, and Bhoja probably originated around the 8th century, reflecting events that had taken place 700–800 years earlier.

Who started these calendars, we may never know. Their historical origins have long been overshadowed by the legends. But legends are critical to culture. Stories shape our identity.