His baptism index:

First name(s) Thomas Costa
Last name Longman
Birth year 1828
Baptism year 1828
Baptism date 02 Jan 1828
Baptism place Sherborne
Parents' name(s) Son of John & Sarah
Father's first name(s) -
Mother's first name(s) -
Notes Druggist
County Dorset
Country England
Record set Dorset Baptisms
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This record is to be found in the India Office:

First name(s) Thomas Coster
Last name Longman
Event year 1855
Presidency Bengal
Death year -
Place -
Record type Administration
Archive reference L-AG-34-29-92
Page/folio number 273 & 274
Catalogue description Wills - Bengal 1780-1938
Record set British India Office wills & probate

The scan of the original is on FindMyPast but I cannot make sense of it!
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He was in the 1851 census, a solicitor born in Sherborne, Dorset, with his widowed mother, sister and brother unmarried living in Westbourne Place, Westminster, Mx.

He was not in any subsequent census and might well have died in 1855 as in the above India Office record.
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BUT, in the Probate Index for 1954, there is an entry for the will of Freda Christine Marie Coster-Longman who died on 19 June 1955 and whose Administrator was Clifford Morris Coster-Longman, incorporated accountant.

Her death index shows her to have been born around 1881:
Surname First name(s) Age District Vol Page
Deaths Sep 1955   (>99%)
Longman Frieda C M C 74 Lewisham 5d  15
Coster-Longman Frieda C M 74 Lewisham 5d  15

This led nowhere!  So I have given her up as an unsolved mystery.

Mystery No 2 is a further Coster-Longman, in the form of this marriage:

First name(s) GORDON J
Last name COSTER-LONGMAN
Marriage quarter 4
Marriage year 1943
Registration month -
MarriageFinder™ GORDON J COSTER-LONGMAN married
MARION L COPE
Spouse's last name COPE
District DERBY
District number -
County Derbyshire
Country England
Volume 7B
Page 1235
Record set England & Wales marriages 1837-2008

His death index was:

First name(s) GORDON JOHN
Last name COSTER-LONGMAN
Gender Male
Birth day 5
Birth month 2
Birth year 1916
Age -
Death quarter 3
Death year 1986
District SOUTHWARK
Register number 986
County London
Volume 15
Page 143
Country England
Record set England & Wales deaths 1837-2007

This gave a birth, on this planet of 5th February 1916.  But no record found on FindMyPast.

However the 1939 Register showed up a family of Coster-Longmans in Lewisham, London:

Coster-Longman Household (5 People)
74 Belmont Hill , Lewisham, London, England

FIRST NAME(S) LAST NAME(S) DOB SEX OCCUPATION MARITAL STATUS  SCHEDULE  SCHEDULE SUB NUMBER

John Coster-Longman 09 Dec 1876 Male Florist Married  47  1
Frederick C Coster-Longman 07 Oct 1880 Male Unpaid Domestic Duties  Married  47  2
Doreen H M Johnson 15 Oct 1911 Female Unpaid Domestic Duties  Single  47  3
Gordon J Coster-Longman 05 Feb 1916 Male Qualiied Company Secretary  Single  47  4
Clifford M Longman (Coster-Longman) 13 Jul 1914 Male  Qualified Company Secretary  Single  47 5

I think, with the above five people put in the order of their sub-number, that ‘Frederick C’ was incorrectly classified as male.  A confirmation of this is the Probate record for John Coster-Longman in 1944 when Freda Coster-Longman obtained probate for John and was described as ‘widow’.

From this last, I surmise that John C-L was the father of Gordon John C-L.  John was born, as in the 1939 Register above, on 9th Dec 1876 and let’s see what we can find for that.  But nothing found for his birth or in any census.  He has to have been abroad before 1939 and possibly born abroad.

There are one or two modern Coster-Longmans floating around the internet; but no e-addre4sses, only facebook.

The only Coster-Longman births on FreeBMD are probably still alive:

Surname First name(s) Mother District Vol Page
Births Sep 1944   (>99%)
Coster-Longman Christina L Cope Derby 7b 1089
Births Jun 1949   (>99%)
Coster-Longman Julia M Cope Bromley 5b 117

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The London Gazette seems to have the answer.  On 5 April 1932 in issue 33814, p. 2211, there is this entry under Naturalisations:

“Lengemann, Johannes (known as John Coster and John Coster-Longman); No Nationality; Florist; 41 Clarendon Road, Lewisham, London.  4 March 1932.”

This list of names in alphabetical order had this heading:

NATURALISATION

LIST of ALIENS to whom Certificates of Naturalisation have been granted by the Secretary of State and whose Oaths of Allegiance have been registered in the Home Office during the month of March 1932.
The date shown in each case is the date on which the Oath of Allegiance was taken.

In other words, all the above has been a wild goose chase.
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