The name probably came from SǷetman or Suetman which was based on latin for 'sweetman' (nice person!).
In the UK, there are several separate groups named Sweatman and only the Oxfordshire, Warwickshire and Manchester families can be linked. The south and south
eastern groups in the UK cannot yet be linked to the Oxford 'clan' - help required please!
Over the centuries it appears in various forms such as Swetman, Swetnam and Sweatman. As most people could not write, the scribes had a free hand in writing
it down. As very few could read.... then who could argue anyway!