Sticking my neck out slightly, yes there are plenty of Robert Martins, but as you know William Martin son of Robert, was born in Drumreagh 16 January 1855. So sticking to your knowledge Robert was a farmer and presumably in Drumreagh and farmers don’t move about that often. What are the available records for Martins in Drumreagh.
From Ros davies Co Down website
Alexander MARTIN . Killinchy family burying place c. 1850 at Ballymacashen Reformed Presbyterian graveyard MIs
Alexander MARTIN . Killinchy born 15 Jul 1803; husband of Christian; father of Catherine, Mary L. & Nathaniel & Caroline; died 6 Mar 1895; buried Ballymacashen Reformed Presbyterian graveyard MIs
Lowry MARTIN . Killinchy of Drumreagh; died 19 Aug 1900 aged 51; son of Robert & Anne Jane Martin; buried Ballymacashen Reformed Presbyterian graveyard MIs
Jim notes Lowry MARTIN b 1849
Nathaniel Carr MARTIN . Killinchy born 11 Dec 1854; son of Alexander & Christian; d. 25 Mar 1888; buried Ballymacashen Reformed Presbyterian graveyard MIs
Robert MARTIN . Killinchy of Drumreagh; died aged 48; husband of Anne Jane who d. 20 Dec 1848 aged 25; father of Jane & Lowry; buried Ballymacashen Reformed Presbyterian graveyard MIs
Robert MARTIN . Killinchy in Ballymacashen; leased a house & garden from Matthew William Lowry in 1863 GV
So that suggests that they nearly all must be members of Ballymacashen Reformed Presbyterian.
Marriage records in the area go strange after 1845, as Government takes an interest. I doubt if further church marriage records would have all been pulped. So lets guess that the marriage is between 1845 and 1856.
Ros Davies records the Presbyterians and their records in Killinchy Parish as follows 1st Presbyterian Church in Balloo townland Records available are baptisms 1812- 1837 & births 1835- 1900, marriages 1812- 1845, PRONI MIC/1P/404
From 2nd or Reformed Presbyterian Church, Ballymacashin, on the Killinchy to Saintfield road {The 1st Presbyterian church divided on doctrine. They met in a barn until the church could be built in 1847. 400 people attended this church in 1833. In 1864 the sexton's house & yard was next door. Also known as Killinchy R. P. Church. Records available are marriages 1835-1845;
Presbyterian Non Subscribing Church (Remonstrant) in Balloo townland, on the Killinchy to Saintfield road Records not mentioned.
Griffiths Valuation of Ireland probably 1863 has only
Surname First Name Townland Parish County
Following are the exact matches:
Martin Jane Ballymacreelly Killinchy Down
Martin John Aughnadarragh Killinchy Down
Martin John Barnamaghery Killinchy Down
Martin Mary Anne Ballymacreelly Killinchy Down
Martin Robert Ballymacashen Killinchy Down
Martin Robert Ballymacreelly Killinchy Down
Martin Robert Drumreagh Killinchy Down
I had hoped the last one would turn out to be a farmer, however Ros Davies last entry says GV was for a house and garden.entry
Most farmers ended up listed at PRONI’s freeholders I wanted to see who else in Drumreagh was a freeholder but I couldn’t get onto to their new layout at applications.proni.gov.uk/Freeholders/default.aspx today. If you get to a convenient entry the detail sometimes mentions who is in line for the farm if the farmer dies. Wife, sons etc. That search is important to do.
Have you used
www.familysearch.comHave you used the Ulster Historical Foundation ie ancestryireland etc
Have you used
www.emeraldancestors.comFinally have you seen the entry for William Martin in the Presbyterian Fasti of Ireland.
So trying to encourage you no to get lost in to many Robert Martins, the problem might be he didnt marry in his own church but at the wifes. Margarets birthcertificate would be interesting.
Good luck, Jim