A by-election was held for the New South Wales Legislative Assembly electorate of Cumberland South Riding on 21 August 1856 because Elias Weekes resigned in August 1856 after winning his appeal against his defeat in Northumberland Boroughs.
|9 April 1856||Elias Weekes elected at the election for Cumberland (South Riding)|
|22 May 1856||Elias Weekes sworn in as a member for Cumberland (South Riding)|
|24 June 1856||Committee of Elections and Qualifications declared that Elias Weekes had been elected for Northumberland.|
|5 August 1856||Next sitting day of the Legislative Assembly and the report of the Committee of Elections and Qualifications was printed.|
|Elias Weeks resigned as a member for Cumberland (South Riding).|
|6 August 1856||Writ of election issued by the Speaker of the Legislative Assembly.|
|18 August 1856||Nominations at Parramatta|
|21 August 1856||Polling day between 9 am and 4 pm.|
|27 August 1856||Return of writ|
|Ryan Brenan (elected)||435||42.7|
|Thomas W Shepherd||110||10.8|
|Total formal votes||1,019||100.0|
- Green, Antony. "August 1856 Cumberland (South Riding) by-election". New South Wales Election Results 1856-2007. Parliament of New South Wales. Retrieved 12 June 2019.
- "The Northumberland Boroughs election". The Maitland Mercury and Hunter River General Advertiser. 26 June 1856. p. 2. Retrieved 20 September 2020 – via Trove.
- "Report from the Committee of Elections and Qualifications, in the matter of the petition against the election and return of Bourn Russell Esq". The Maitland Mercury and Hunter River General Advertiser. 16 August 1856. p. 6 (Supplement to the Maitland Mercury). Retrieved 20 September 2020 – via Trove.
- "Committee of Elections and Qualifications". The Empire. 6 August 1856. p. 2. Retrieved 20 September 2020 – via Trove.
- "Mr Elias Weekes (1809–1881)". Former Members of the Parliament of New South Wales. Retrieved 22 May 2019.
- "Writ of election: South Riding of Cumberland". New South Wales Government Gazette. No. 120. 8 August 1856. p. 2151. Retrieved 24 June 2021 – via Trove.