A street in east Belfast, in existence by at least 1890, when it is recorded in the Belfast News-Letter (2 October 1890) in connection with the erection of 22 houses in Glentoran Street, Rathmore Street, and Mount Street for R. J. Dawson. These streets were laid out on lands forming part of the Coates estate at Lagan Village, centred on “Glentoran,” a substantial house occupied by William Coates and his family; the house had previously been known as Snugbrooke, appearing under that name on late eighteenth-century mapping before being renamed by the early nineteenth century.
The name Rathmore Street derives from Rathmore House, built in 1865 at nearby Dunmurry by Victor Coates, who had purchased approximately 170 acres and developed it as a private estate; the name “Rathmore” (Irish Ráth Mór) meaning “great fort.” The house was situated east of Dunmurry village, off Dunmurry Lane. The building and the site are now occupied by Rathmore Grammar School. Rathmore Avenue, Rathmore Gardens and Rathmore Park are nearby in the Erinvale estate.
Ground rents in Rathmore Street and neighbouring streets formed part of the Coates estate and were still being sold as such in 1933 (Northern Whig, 2 December 1933).
Sources:
Belfast News-Letter, 2 October 1890.
Northern Whig, 2 December 1933.
Williamson, Map of Belfast (1791).
History Hub Ulster (Victor Coates).