I can’t find his birth on FreeBMD around 1856 but there is a Fred Hamilton born in Q2 of 1854 in St Pancras district, vol 1b, p. 201.
I cannot find his death on FreeBMD up to 1910.  2016: But see below.
I cannot find him on the 1881 census.

In 1919 he was alive enough to write a sympathetic letter to The Times on the problems of the coloured population of Cardiff.  He wrote as President of the Cardiff World Mission. See Times of 24 Jun 1919.

In 1911 he was with his wife and no children, reporting that she had never had any:

Name Relation Condition/ Yrs married Sex Age Birth Year  Occupation  Where Born

HAMILTON, Frederick H Cowrey Head Married M 54 1857   Solicitor  Scogford Norfolk
HAMILTON, Geraldine Wife Married 24 years F 53 1858  Dublin(eh?)
WEBB, Alice Cook Single F 48 1863 Cook Domestic  Gloucestershire, Swindon
TRUTCH, Bessie Servants Parlourmaid Single F 23 1888  Parlourmaid Domestic  Ensmore Somerset
FOX, Florence Servants Sewingmaid Single F 27  1884 Sewing-Maid Domestic  Monmouthshire Benly
TANNER, Alice Servants Laundrymaid Single F 27  1884 Laundry-Maid Domestic  Glamorgan Cardiff
HILL, Cartherine Laundry Maid Visitor Single F 22  1889 Laundry-Maid Domestic  Birkenhead

RG number: RG14 Piece: 32051
Reference: RG14PN32051 RG78PN1844 RD588 SD1 ED7 SN97

Registration District: Cardiff
Sub District: Llandaff
EnumerationDistrict: 7
Parish: St Fagans

Address: Tyla Morris St Fagans
County:   Glamorganshire
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Not found in the 1939 Register:
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He had sundry holdings in GWR shares.
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His death index:

First name(s) FREDERICK DE C
Last name HAMILTON
Gender Male
Birth year 1857
Age 83
Death quarter 1
Death year 1940
District EAST GLAMORGAN
County Glamorganshire
Volume 11A
Page 1944
Country Wales
Record set England & Wales deaths 1837-2007
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His burial index:

First name(s) FREDERICK DE COURCY
Last name HAMILTON
Birth year 1856
Death year 1940
Death day 27
Death month Mar
Age at death 84
Parish ST.NICHOLAS
County Glamorganshire
Country Wales
Burial place St.Nicholas
O S grid reference ST 090743
Record set Glamorgan Monumental Inscription index
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Jan 2017: Caroline Collett has written with these gems:

“I have a note from Glamorgan Archives that Frederick de Courcy Hamilton of Tyla Morris was born 1856 died 1940.

“I have his book ‘The Eternal Quest, a Scroll of Empires’ dated 1924 and signed by him. 
“I remember seeing in Tyla Morris a portrait of him on an easel. Might have been a self portrait!
There is a book in Glamorgan Archives called ‘A Cardiff Soliitor and Docksman’.”
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This led to actually finding him in the 1939 Register:

Hamilton Household (5 People)
Tyla Morris Lodge Pentyrch , Cardiff R.D., Glamorganshire, Wales

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

Bessie M Stephens 30 Jul 1898 Female Private Secretary  Single  4  2
Frederick De L Hamilton 23 Jun 1856 Male Solicitor & Company Manager  Widowed  4  1
Mary Williams 22 Feb 1870 Female Parlour Maid Single  4  3
Annie L Cross (Walden) 23 Dec 1919 Female Cook Single  4  4
Ernest Lowe 24 Mar 1884 Male Valet Married 4 6

Bessie May Stephens was left the house in his will, for which see the probate entry.
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His probate index:

HAMILTON Frederick de Courcy of Tyla Morris Pentych Glamorganshire died 27 March 1940 Probate Llandaff 11 July to Fanny Louisa Hamilton and Bessie May Stephense spinsters.
Effects £46223 15s 9d. in England.

Fanny Louisa was his slightly younger sister.  No idea about Bessie May.

Apparently she was the Sunday School teacher and inherited Tyla Norris.  This is probably her birth index:

First name(s) BESSIE MAY
Last name STEPHENS
Birth year 1898
Birth quarter 3
District PONTYPRIDD
County Glamorganshire
Country Wales
Volume 11A
Page 568
Record set England & Wales births 1837-2006

This is definitely her, and him, in the 1939 Register:

Hamilton Household (5 People)
Tyla Morris Lodge Pentyrch , Cardiff R.D., Glamorganshire, Wales

FIRST NAME(S) LAST NAME(S) DOB SEX OCCUPATION MARITAL STATUS  SCHEDULE  SCHEDULE SUB NUMBER
Bessie M Stephens 30 Jul 1898 Female Private Secretary  Single  4  2
Frederick De L Hamilton 23 Jun 1856 Male Solicitor & Company Manager  Widowed  4  1
Mary Williams 22 Feb 1870 Female Parlour Maid Single  4  3
Annie L Cross (Walden) 23 Dec 1919 Female Cook Single  4  4
Ernest Lowe 24 Mar 1884 Male Valet Married 4 6

And this is likely to be her death index:

First name(s) BESSIE MAY
Last name STEPHENS
Gender Female
Birth day 30
Birth month 7
Birth year 1898
Death quarter 3
Death year 1985
District SOUTH GLAMORGAN
Register number 985
County Glamorganshire
Volume 28
Page 1950
Country Wales
Record set England & Wales deaths 1837-2007

And her probate index looks like:

STEPHENS, Bessie May of St Winifred’s Hospital Romilly Cres Cardiff died 5 September 1985 Probate Llandaff 9 October £309785  8551805640Z
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Their marriage index:

Surname First name(s) District Vol Page
Marriages Jun 1886   (>99%)
Hamilton Frederick Deboursey Elham 2a 1527

The ‘Deboursey’ is what is on the marriage index itself.
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