Countries who have had at least one driver start at least one F1 GP:
(compiled this list some time ago using GP Data Book and Autocourse)
Europe:
UK
Italy
France
Germany
Austria
Finland
Belgium
Switzerland
Sweden
Netherlands
Spain
Republic of Ireland
Portugal
Denmark
Monaco
Liechtenstein (
Rikky van Opel)
Czech Republic (Tomas Enge)
Asia:
Japan
Malaysia (Alex Yoong)
Thailand (B Bira)
Americas:
Brazil
USA
Argentina
Canada
Mexico
Colombia (JPM, Roberto Guererro)
Chile (Eliseo Salazar)
Venezuela (Johnny Cecotto)
Uruguay (
Alberto Uria,
Oscar Gonzalez)
Africa:
South Africa
Zimbabwe/Rhodesia (
John Love,
Sam Tingle)
Oceania:
Australia
New Zealand