I got curious and wanted to check Tolkappiyam because it is one of the accepted works in Tamil literature. This is the first paragraph in its English translation by Thiru (Dr) V. Murugan. first edition printed in 2000. V. Murugan garu opens his Introduction by saying "Tolkappiyam, a comprehe...... written by Tolkappiyar, dates back to at least a few centuries before the dawn of Christian era". (I personally prefer referring to as the Jesusism era). In the same opening paragraph, he says there are 240 references to earlier authorities. This has to be kept in mind. Now, the next question is the Brahminism of Tolkappiyar. Let us see what the book unfolds. Now, I will keep adding to this thread.
Brahminism arrived in South India around the same time as Christianity. In some parts, even Islam predates its arrival. The "Hinduism" we see today in the south is Brahminism colonizing the native deities and forms of worship, further reinforced under the British rule.