Prefatory Note: I too wish, much like the author, I had the benefit of time, and hence, my apologies for being brief and sketchy.
This is an important book for two reasons described by its author. First, she says that history - I guess, much like every other discipline - is not meant to be instructive and all well-intended talk about forgetting history and repeating old blunders is too lofty. There is no reason to believe that Boris Johnson was all the wiser for being a biographer of Churchill, or Buddhadeb Bhattacharjee more astute in Nandigram having witnessed the slaughter at Marichajhhappi. To know history is to know where we come from. As Sarvapalli Radhakrishnan wrote, the study of early human society was to see the first, tottering, tentative steps of mankind (the words are not exact but the sense is spot on). Second, Upinder Singh agreeably emphasises on the importance of gleaning history by reading from first-hand sources and texts. In a world where all wisdom is received wisdom from translations in English prose, where Dharmashastras and ancient texts are transcribed by scholars whose grasp of the language is dangerously shaky and tenuous, I cannot think of anything more well-meaning in the study of ancient people speaking in alien tongues.
Alas! She relies on translations, which makes me wonder whether her own knowledge of the ancient sources is derivative and not based on the actual sources. While the book does not burden us with platitudes, much of it is not new and her many ideas seem like trodden paths. There are refreshing exceptions. In the chapter on romance in ancient India, she talks about love graffiti inscribed on the walls of caves by, I presume, romantics, tumescent adolescents & heartbroken ancient Sahirs. I was most fascinated by the section on a certain genre of Tamil poems, abounding with double entendres, implicit meanings and whatnots.
In the passages on women, the historian's probe was sadly defective. There was nothing revelatory, though her observation that these texts, often the work of several individuals over long stretches of time, contained contradicting beliefs and that it was quite difficult to impute a certain slant to the text, even though some stuff contained in them was undeniably twisted, appears reasonable. But the examples were few and did not buttress her arguments. Which is why it appears to me that the book was written in undue haste (it was written during the lockdown) and I will welcome future revisions, where she wholly rewrites at least 3 of the 5 chapters.