Joseph Nelson

Tradition was to marry in the bride’s church so that suggests Jane Johnston may have been a member of Garvagh 1st Presbyterian church. Their baptism and marriage records start in 1795 (with some gaps) so you may be able to find her baptism and that of any siblings in those records. Joseph may also have been a member of that congregation so worth checking for him too. There’s a copy of the records in PRONI (the public record office) in Belfast. It includes a census of the congregation in 1796 and another in 1840, both of which might be useful to you.

Tithe applotment records for Errigal in 1825 list a David Nelson senior and a David jnr in Gortnamoyagh townland:

http://www.irishgenealogyhub.com/derry/tithe-applotments/errigal-parish.php#.V4k5Rzd9eg0

1831 census for that townland shows 3 Nelson households. David junior with 1 male and 3 females; another David junior with 4 males and 4 females and Joseph with 2 males and 1 female. All Presbyterian.

Probate abstract:

The Will of Joseph Nilson late of Gortnamoyagh County Londonderry Farmer deceased who died 1 January 1872 at same place was proved at Londonderry by the oath of Elizabeth Johnston of Gortnamoyagh (Garvagh) aforesaid Spinster the sole Executrix according to the tenor. (Limited Grant.)

The will itself is on-line on the PRONI wills site. Joseph was 64 when he died.

This looks to be that property in the 1901 census:

http://www.census.nationalarchives.ie/pages/1901/Londonderry/Glenkeen/Gortnamoyagh/1520253/

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