Ireland and Great Britain – Smith, Smyth, Smythe, Smithson, Smeaton, Smither(s), Gow, Gowen, Gowan(s), McGowan, McGowing, McGown.
Germany and Austria – Schmidt (and variations of this).
Scandinavian countries – Smedbakken, Smedstuen, etc.
Spain (and Spanish-speaking regions) – Hernández, Fernández.
France (and French-speaking regions) – Le Fèvre, Lefèvre, La Forge.
Portugal (and Portuguese-speaking regions) – Ferreiro.
Hungary – Kovács.
Russia – Kuztnetsov.
Arab countries – Haddad.
The ‘Smith‘ type names found in north-west Europe come from the old Germanic verb smíðan (to smite, hit, strike, forge).
The ‘fer/her‘ type names found in France, Spain and Portugal come from the Latin word ‘ferrum’ (iron).
The ‘gow‘ forms are from Gaelic, the prefix ‘Mc’ or ‘Mac’ giving the meaning “son of”. Such names we would expect to find in the greatest numbers in Ireland and Scotland, though emigration has taken the name to North America, Australia, New Zealand and all parts of the United Kingdom (e.g. the Member of the European Parliament for Leeds, West Yorkshire, in the 1990s : Michael McGowan).
The Cambridge Encyclopedia of Language (1987) by David Crystal; Cambridge University Press, Cambridge, UK
Dictionary of Surnames (1978) (Second edition) by Basil Cottle; Penguin Books, London.