This is the photo of the Malayalam calendar hanging in my house and as per that calendar, the year is 1189 which means that something important happened in 825 CE. Wikipedia mentions that the important event was the establishment of a Nestorian colony. Maddy has written about various other events and that is covered in A Survey of Kerala History by A Sreedhara Menon as well. The book Perumals of Kerala by Prof. M.G.S. Narayanan deals with these issues and comes up with an answer while refuting few others.
But before getting to the origins of the Malayalam calendar, called the Kollam Era, it is important to understand how events were recorded in India. The date on which the event occurred was mostly tied to a seminal event such as the establishment of a temple or an important marker like the beginning of the Kaliyuga or the Hijra. The position of Jupiter, the position of sun, the date, the week day and the nakshatra were noted while recording events. Another popular way of recording events was to base it on reginal years of the king. Thus, if you were writing about the recent Indian elections, you would write, “In the 1st year of Rahul Gandhi being the Vice-President of Indian National Congress, it had just enough MPs under the Whatsapp group limit” or “In the 9th year of Prakash Karat’s tenure as CPI(M) general secretary, the party won seats which could be counted using both hands.”
The problem with reginal years or the establishment of a temple is that the events were local and that makes it hard for people outside the region to make sense of the date. But sometimes a local event can achieve such significance that it can live on for a thousand years and one such event happened in the southern part of Kerala.
Around the 8th century, there existed the region between Tiruvalla and Nagercoil was known as Vēṇāṭ with its capital at Vizhinjam. In the 8th century, the Pandyans made an expansionist move and to counter that the Cēra forces moved to the south. They took over Vēṇāṭ, absorbed it into the Cēra kingdom and established Kollam as the capital. This was an important victory for the Cēra’s with political and economic consequences. Kollam was a harbor city and remained important from the 9th to the 12th centuries and it was from here that the Chinese trade really took off. Eventually that trade would move up to Cochin and then Calicut. Marco Polo visited Kollam in 1294, Jordan Catalani in 1330 and Ibn Batuta in 1343 an all of them mentioned the Chinese presence there. As Kollam bought in prosperity, its establishment became significant and what started out as a local era, was used in Vēṇāṭ and eventually the whole of Kerala, though the port of Kollam became less important to Calicut eventually.
There are two inscriptions from this period, found in Kollam, which mention the phrase “Kollam tonri” implying that the event happened after the inauguration of Kollam. Some historians have suggested — based on letters by the Nestorian Patriarch of Babylon — that the city of Kollam existed before 825 CE. Narayanan writes that this is based on an arbitrary and erroneous reading of Latin. Another suggestion is that “Koulam Male” was mentioned in Cosmas Indicopleustes by a 6th century Alexandrian merchant. Narayanan thinks that this refers to Kolam or Kolapattanam in North Kerala. Ma Huan wrote that the Tang dynasty knew about Kollam, but it may be about knowledge closer to the 9th century.
The Nestorian date is related to the settlement of Christian traders under the leadership of Mar Sapir Iso and that has been advanced by historians. According to them, if modern India could adopt Christian era, then it was possible a millennium back as well. Narayanan dismisses that argument; according to him, the establishment of Kollam as an important city came first followed by the establishment of the Nestorian colony. Narayanan writes that this incident would not have been universally acceptable compared to the founding of the city. He also dismisses the theories that it was associated with the departure of Cheraman Perumal to Mecca (a myth) or with Shankaracharya.
- Perumals of Kerala by Prof. M G S Narayanan