The 1934 Monmouth by-election was a by-election held for the British House of Commons constituency of Monmouth in Wales on 14 June 1934. It was won by the Conservative candidate John Herbert.
Vacancy.
The seat had become vacant on when the sitting Conservative Member of Parliament (MP), Sir Leolin Forestier-Walker had died at the age of 68 on 13 May 1934. He had held the seat since the 1918 general election.
Previous result.
! scope="col" colspan="2" style="width: 130px"|Party
! scope="col" style="width: 17em"|Candidate
! scope="col" style="width: 5em"|Votes
! scope="col" style="width: 3.5em"|%
! scope="col" style="width: 3.5em"| ;templatestyles src="Template:Tooltip/styles.css" / ;±%
! colspan="3" style="text-align: right; margin-right: 0.5em" | Majority
! colspan="3" style="text-align: right; margin-right: 0.5em" scope=row | Turnout
! colspan="3" style="text-align:right;" scope=row | Registered electors
! style="text-align:right;" | Swing
Candidates.
The Conservative candidate was 39-year-old John Arthur Herbert.
The Labour Party candidate was Rev. D Hughes, who had been the unsuccessful candidate at the 1931 general election.
Result.
On a reduced turnout, Herbert held the seat for the Conservatives, with a comfortable majority of nearly 10,000 votes. He was re-elected in 1935, but resigned in 1939 to become Governor of Bengal.
! scope="col" colspan="2" style="width: 130px"|Party
! scope="col" style="width: 17em"|Candidate
! scope="col" style="width: 5em"|Votes
! scope="col" style="width: 3.5em"|%
! scope="col" style="width: 3.5em"| ;templatestyles src="Template:Tooltip/styles.css" / ;±%
! colspan="3" style="text-align: right; margin-right: 0.5em" | Majority
! colspan="3" style="text-align: right; margin-right: 0.5em" scope=row | Turnout
! colspan="3" style="text-align:right;" scope=row | Registered electors
! style="text-align:right;" | Swing
References.
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