The Celtic origin of the word Clock is a strong indicator that mechanical clocks were first built in the celtic speaking parts of the UK. Other indicators are the surviving early cathederal clocks, all West of England, and the really quite complicated mechanism used in the even earlier 13th century church clock in Ottery St Mary, Devon.
It's a fascinating subject and one I've looked into quite a lot. For instance, why do we have 24 hours in a day and 60 minutes in an hour. That's thanks to the Sumerians and their use of a duodecimal (base 12) numbering system long before the world decided that since we have 10 fingers it would be good to count in base 10.
Going a bit further, once you can build complicated mechanical machines, then it's not a huge leap to build a complicated mechanical machine that use steam to power it in order to solve the problem of water ingress into deep mines. The start of the industrial revolution, with the first steam engined by Thomas Newcomen, of Devon.
I wrote up my, no doubt biased, thoughts and opinions on the following link.
https://marinechronometer.co.uk/inde...-a-watch-works