United Kingdom by-election records
Parliamentary by-elections in the United Kingdom occur when a Member of Parliament (MP) vacates a House of Commons seat (due to resignation, death, disqualification or expulsion) during the course of a parliament. == Scope of these records == Although the history of Parliament is much older, most of these records concern only the period since 1945.
Source: Wikipedia — United Kingdom by-election records (CC BY-SA 4.0)