Overseas indexes

If your ancestors lived in a country that was formerly a British colony, it's likely that their births, marriages and deaths were registered under the system of the particular country and it will be necessary for you to contact the relevant agency in country concerned.
Cyndi's List contains many thousands of links to help with tracing worldwide genealogy.

There is also a separate series of the General Register Office indexes that includes records of some births, marriages and deaths of British nationals abroad. The following information is held at Wolverhampton Archives & Local Studies :

Births

Army returns 1796-1965
Regimental returns 1761-1924
Ionian Islands (civil and regimental) 1818-1864

Air births 1949-1965
(on any aircraft registered in Great Britain & N. Ireland)
Marine births 1837-1965
(on any ship registered in Great Britain & N. Ireland)

Consular returns 1849-1965
UK High Commission returns prior to 1981
Births abroad 1966-1994

Marriages

Army returns 1796-1965
Ionian Islands (civil and regimental) 1818-1864
Consular returns 1849-1965

UK High Commission and Article 18 marriage deposits
Marriages abroad 1966-1994

Deaths

Army returns 1796-1965
Ionian Islands (civil and regimental) 1818-1864

Air deaths 1949-1965
(on any aircraft registered in Great Britain & N. Ireland)
Marine births 1837-1965
(on any ship registered in Great Britain & N. Ireland)

Consular returns 1849-1965
UK High Commission returns 1950-1965
Births abroad 1966-1994

War Deaths

Boer War 1899-1902
First World War 1914-1921
Second World War 1939-1948

(These indexes include deaths after the wars which have resulted from injuries received in conflicts)