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Identity Statement

Reference code(s): GB 0074 CLC/B/108
Held at: London Metropolitan Archives
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Date(s): 1856-1974
Level of description: Collection
Extent: 35 production units.
Name of creator(s): Guinness, Mahon and Co | bankers


Administrative/Biographical history:

Guinness and Mahon, land agents, was established in Dublin in 1836 by Robert Rundell Guinness (1789-1857) and John Ross Mahon (1814-1887). Within a short time, banking became the firm's main concern. It was renamed Guinness, Mahon and Company in 1851 and a London agency was opened in 1873. In 1916 three of Robert Rundell Guinness's grandsons retired from the firm following the death of their father, Richard Seymour Guinness, and the London office was closed. Their cousin, Howard Rundell Guinness was left with the small banking firm in Dublin. The London office was reopened in 1923 by Howard Rundell Guinness and his three sons (Henry Samuel Howard Guinness, Edward Douglas Guinness and Arthur Rundell Guinness, who became partners in the firm).

The firm in Ireland was registered as a private unlimited company in 1942, with the name Guinness and Mahon. The London business was henceforth called Guinness, Mahon and Company. In 1963 Viking International Corporation Limited (previously known as Viking Tanker Company Limited) acquired all the share capital of Guinness, Mahon and Company. Viking International Corporation Limited was renamed Guinness Mahon Holdings Limited. In 1973 Guinness Mahon Holdings Limited and Guinness, Mahon and Company Limited were acquired by Lewis and Peat Limited. The new holding company was called Guinness Peat Group Limited. The merchant bank, Guinness, Mahon & Company, continued business under the same name. In 1988 Guinness Peat Group was demerged into three groups: Guinness Mahon Holdings comprising the Guinness Mahon merchant bank and related investment management; Fenchurch Insurance; and off-shore activities. In 1991 the Bank of Yokohama acquired full ownership of Guinness Mahon Holdings. In 1998 it was sold to Investec of South Africa.

The London firm was based at St Swithin's Lane ([1873]-1901), 81 Lombard Street (1902-1916), 20 Bishopsgate ([1923]-1926), 53 Cornhill (1927-1964), 3 Gracechurch Street (1964-[1976]), 32 St Mary at Hill ([1976]-).


Scope and content/abstract:

Records of Guinness, Mahon and Company, mainly comprising correspondence between partners, but there are also memorandum and articles of association, 1956-1966 (Ms 38588); agreements and related papers, 1856-1893 (Ms 38589); board minutes and interim accounts, 1966-8 (Ms 38590); and papers relating to the Guinness family, 1924-69 (Ms 38612).

Henry Samuel Howard Guinness (1888-1975), usually referred to in the papers as "S.G.", was a director of Guinness and Mahon Limited, Dublin, and a senior partner in Guinness, Mahon and Company, London. It appears that he wrote many of the notes on the history of the firm and the Guinness family which can be found in this collection. Some of the bundles and files of papers may also have been compiled by him.

Access & Use

Language/scripts of material:

System of arrangement:

Records arranged by MS number, assigned during cataloguing at the Guildhall Library Manuscripts Section.

Conditions governing access:

Available for general access.

Conditions governing reproduction:

Copyright to this collection rests with the City of London.

Finding aids:

Please see online catalogues at:

Archival Information

Archival history:

Immediate source of acquisition:

These papers were donated to the Manuscripts Section of Guildhall Library in 2006 by a descendant of the Guinness family. The Guildhall Library Manuscripts Section merged with the London Metropolitan Archives in 2009.

Allied Materials

Related material:

The National Library of Ireland holds letterbooks 1837-1925 of Guinness, Mahon & Company.

Publication note:

Description Notes

Archivist's note:

Rules or conventions:
Compiled in compliance with General International Standard Archival Description, ISAD(G), second edition, 2000; National Council on Archives Rules for the Construction of Personal, Place and Corporate Names, 1997.

Date(s) of descriptions:
November 2010 to January 2011.

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