BrasilBase The Brazilian database by Adaucto Wanderley da Nóbrega.
BritBase John Saunders’ archive of British tournaments. One of the first national databases and one of the best.
ChessBase Probably the biggest online database – but errors do occur.
Chess Notes The chess history site by Edward Winter – one of the best resources online.
Delpher The Dutch newspaper archive. A very useful resource.
Héritage des Échecs Français A site by Dominique Thimognier about chess life in France. A very well sourced site.
Historia del Ajedrez Español A very nice webpage by Mr. Cordero about chess in Spain. Also includes some old magazines.
IRLChess Lots of information about chess in Ireland.
La grande storia degli scacchi All sorts of crosstables – unfortunately without sources.
Olimpbase The high quality site for team chess by Wojciech Bartelski.
Stere.ro A Romanian website with a massive amount of old magazines, books, and bulletins.