Prior to its uniform adoption of proportional representation in 1999, the United Kingdom used first-past-the-post for the European elections in England, Scotland and Wales. The European Parliament constituencies used under that system were smaller than the later regional constituencies and only had one Member of the European Parliament each.
The constituency of London South East was one of them.
When it was created in England in 1979, it consisted of the Westminster Parliament constituencies of Beckenham, Bexleyheath, Chislehurst, Erith and Crayford, Orpington, Ravensbourne, Sidcup, Woolwich East and Woolwich West.
United Kingdom Parliamentary constituencies were redrawn in 1983 and the European constituencies were altered to reflect this. The new seat comprised the following Westminster constituencies: Beckenham, Bexleyheath, Chislehurst, Eltham, Erith and Crayford, Greenwich, Old Bexley and Sidcup, Orpington, Ravensbourne and Woolwich. These boundaries were used in 1984 and 1989. Greenwich was removed for the 1994 European Parliament election.