Over a number of years I have gathered information relating to the name McKechnie in Ireland. I am setting some out of the salient points for the period before 1860. This data has not all been confirmed by me with original sources.
I hope that this helps others; but would also be very pleased if other researchers were able to add to this and indeed make some of the links which must be there just beneath the surface.
1. Brothers Robert and James McKechnie. Born about 1811 to 1816. I do not know where. Robert married Mary Simpson. James married Mary Logan, who was born in Ireland. All the children that I know of of both couples were born in Ireland between 1838 and 1846. Both Robert and James appear to have died by 1861.
2. Robert McKechnie, President of the NY Typographical Union #6, was born in Co. Armagh on 20 Oct 1834, attended the Academical Institute, apprenticed on the Belfast Whig and emigrated to NewYork in January 1854. His parents were William and Margaret McKechnie. William is said to have been born in Scotland and to have been a soldier. Margaret's maiden name is unknown.
3. John McKechnie was an armoury sergeant in the Renfrewshire Militia. He was discharged on 10 aug 1815 and reenlisted on 18 Aug 1815 in Athlone.
4. Rose McKechnie (nee Murdoch) died in Greenock age 76 on 26 Feb 1895. She was born in Ireland, by inference about 1819. Her son, George McKechnie, was born in Ireland about 1847. Her husband, also George, was an army sergeant and had died by 1871.
5. Robert McKechnie, born in Belfast in 1803, joined the 71st Foot at Glasgow on 19 June 1826. His son William McKechnie was born at Claverhouse Castle (Dundee) on 27 July 1832. He was discharged on 11 March 1846 at Kingston, Ontario.
6. William McKechnie, an army pensioner, died at 22 Upton Street, Belfast, on 5 May 1877 age 62 - hence born about 1815.
7. James McKechnie, a printer, died at 46 Little York Street, Belfast, on 29 Oct 1872 age 75 - hence born about 1797.
8. James McKechnie married Margaret Clark in Belfast on 10 Jan 1830.
9. James McKechnie, born 1806 in Ireland, son of Archibald McKechnie and Sarah McMillan, died Hutchesontown, Glasgow, 17 April 1867. He was married to Sarah McCaughey
10. Of the 50+ Irish born McKechnies (males and unm females) listed in the 1881 Scottish census, 4 gave the IOrish county of their birth
a) Robert McKechnie, Kilbarchan, Renfrewshire, age 37, was born in Co. Antrim
b) William McKechnie, St. Quivox, Ayrshire, age 39, was born in Co. Down
c) John McKechnie, Glasgow, age 56, was born in Co. Antrim
d) William McKechnie, Glasgow, was born in Co. Fermanagh.
12. William McKechnie, army pensioner, son of William, married Anne Norwood (widow; d. of Walter Graham) at Belfast Parish Church on 4 Nov 1846
13. Eliza McKechnie, d. of William McKechnie, army pensioner, married William John Chignall on 7 April 1860 at Holy Trinity Anglican, Belfast.
14. In the 1881 census in Greenock, Alexander McKechnie, 17, born in Ireland, is listed as the nephew of David J. Graham.
15. Griffiths valuation lists no McKechnies. But one McKenzie in Shankill Parish, Antrim, is actually spelled McKechine.