wThere is an Anglo Saxon term Halh as well which is often indicated for the origin of Hal in English place names.
from Wiki for Halesowen:
The manor and town was known as Hala (from the Anglo-Saxon word “halh”, meaning nook or remote valley), until it was gifted by King Henry II to Welsh Prince David Owen and became known as Halas Owen.
I looked up Halesowen once because it is in a region with the “saltiest” river in the UK, an ancient history of salt trading and lots of Sal in local place-names as well, but then saw that the Hal in this case has been attributed to Halh. Nice connection to the Princes of Gwynedd though.
Fascinating coincidence though. Of course, assumptions about place name origins aren’t necessarily correct, so it still might refer to “hal” meaning salt.
Britain has some wonderful place names in general, and I’d love to know more about their history.
I don’t know if this is the known origin of Hal or Halen, but to me it has to go back to the Halstatt culture, when the predominant european languages were Celtic, or even before and in Austria you still have the Hallein mine near Salsburg and some of these salt mines stretch back, before the Halstatt even to 6000BC.
The Halstatt is not supposed to have stretched to Wales, but some Halsatt implements were found in the Llyn fawr horde of 700BC.
Who knows perhaps these were truly Halcyon (Halsian) times for Europe.