From "What's in a name? SLATER" (
http://www.genuki.org.uk/big/eng/DBY/NamesPersonal/Slater.html)
"Are you called SLATER? This is an occupational name and in most cases will have referred to a man who made roofs. The caveat 'most cases' indicates that families with Scots connections and especially if they retain the old spelling 'Sclater' may derive their name from Kirkwall, Orphir or Sanday (Orkneys). There, the use of nicknames prevailed and in this case would have been conferred upon a member of the community who was thought to be sly or cunning. It was derived from the Old Norse 'slottigr' and the earliest example dates from 1492 in the person of Adam Sclater of Orkney.
The name is now usually spelled 'Slater' but 'Sclater' is not infrequent in the north of England and in Scotland where the spelling 'Sklater' was still in use in 1823."
Still no Greeks. Nor Mexicans.