The Gilded Age, the stereotypical example of a time with high inequality (which we have, in fact, now surpassed by any reasonable measure) was in the 19th century in the USA.
We had no hereditary nobility (not in name, anyway). The robber barons were all (to the best of my knowledge) "new money"—their families made their fortunes right here in America by getting in on the ground floor of brand-new industries (very much in the same way that startup founders are trying to do today) as the Industrial Revolution was ramping up...and then becoming monopolists and extracting all the money they could (very much in the same way that startup founders are trying to do today).
We had no hereditary nobility (not in name, anyway). The robber barons were all (to the best of my knowledge) "new money"—their families made their fortunes right here in America by getting in on the ground floor of brand-new industries (very much in the same way that startup founders are trying to do today) as the Industrial Revolution was ramping up...and then becoming monopolists and extracting all the money they could (very much in the same way that startup founders are trying to do today).
You may need to review your history.