Self-importance Well Punctured

Our sense of time is tuned to the everyday: you can’t see your children grow or mountains erode, for the very simple reason that life would be impossible if you could. Genealogy usually keeps a researcher’s nose firmly against this grindstone of the humdrum, and that’s one of its beauties; it is very hard to stray into geological time-scales and grand historical abstractions when you can see individuals and families flagrantly disobeying the laws of statistics before your very eyes. Just occasionally, however, something will poke out from the background that gives a sense of the scale of the invisible changes going on.


The surname “Costello” has more than 70 recorded variant spellings in the records of the past two centuries, from “Castolo” to “Custullo”, (see here) but it has a very precise origin. It was adopted in the 12th century by the children of Jocelyn de Angulo, son of Gilbert, one of the original Norman invaders. There is disagreement as to whether Osdealbhach, the forename at the root of the surname Mac Osdealbhaigh (phonetically “McOStealvy”), is a genuine Gaelic name itself, or a mangled Gaelicisation of ‘Jocelyn’, but there is no doubt at all that this individual was the origin of the modern surname.

Not Abbott

In 1911, around 10,000 individuals in Ireland bore the surname Costello or a variant. A first reaction might be to congratulate Jocelyn on his fecundity, but of course, over 7 centuries, anything up to half-a-million individuals could be the 20-generation ancestors of someone living in 1911, so Jocelyn was only responsible for the surname, not all the genes. Even so, the sheer numbers connected to him both as descendants and co-ancestors give a dizzying glimpse of the complexity of our relatedness.


Nothing punctures your sense of being in charge of your own life quite as thoroughly as a stinking head-cold – I have one at the moment – but genealogy can come a close second.

6 thoughts on “Self-importance Well Punctured”

  1. Awww , bad. I do understand…my nose it won’t blow, 🤧. head big as a house, eyes all gunked up,😵— ears itch, but by gosh the Ragweed is beautiful this time of year! 🌾🌾🌾🌾🌾🌾🌾🌾🌾🌾🌾🌾🌾🌾🌾🌾🌾🌾🌾🌾🌾🌾. AaaaaaaaaaaaChooooo! 😃

  2. Hope you feel better soon and thanks for posting despite the rotten cold. And thanks for the Costello info. It’s in our family by marriage. Most in the US think it’s Italian and maybe Italy has the name independently. Herrick is one of my Irish names. Of course, it is English in origin but there were lots of Germans in the 19c US censuses who were also Herrick.

  3. Love your Blog John. I look forward to the weekly post. A sense of humour is so important in getting through the humdrum that can be daily life.

  4. John, sorry about the head cold. Such a tiny virus wreaking such discomfort!

    Where I am from in New England, Costello is a very common name for the Portuguese immigrant descendants. When first starting this genealogy journey, I was pretty perplexed to find the name Costello in Roscommon. Nice to learn more about it. Thanks!

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