Very educative, interesting, absorbing; and yet a few glaring gaps - for those that know, not everyone. The writer seems unaware of how much languages other than European influenced English, not only due to the colonial history but in fact much more and much longer ago.
Latin and Greek are thought to have stemmed from Sanskrt, and similarity of words between Indian languages and English stems from that much more often than from the liberal borrowing of Indian words staight lifted into English out of necessity of colonial era.
But even more surprisingly the writer is blissfully forgetful of the mediterraenean connections of Europe and west Asia, and when he asks about the enexplicability of roots of the word "bad" and a few others, one is tempted to rap knuckles and say, Arabic or Hebrew, dumbo, obvious, trivial!
Of course such gaps are glaring only because he is so good otherwise, unlike the generic compatriot or even a generic ancestral cousin from across the pond, whether in the isles or the continent ( which is often worse than the isles in this regard).