I have been researching this rather rare surname for some time. One of its sources is the Newport/Nevern area of Pembrokeshire although I know that there was some migration to other parts of the county, to the adjoining Carmarthenshire and possibly the Swansea area. Also, some of the lines ended up in the US and I am in contact with some of the descendants. I would be interested in any information which others have come across. Variations of the surname include : Shaddrach Shadrack Shaddrack Shaderick Shadderick Eirwyn Davies Aberystwyth Wales