Together with YMCA, Frankfort and Rathmines Athletic, they are one of only four clubs to have played just one season in the top level of the League of Ireland.

[1] In early 1934, Shelbourne were fined by the Football Association of Ireland for allegedly poaching players from nearby clubs.

[5] With a team that included Willie Ouchterlonie and Tommy "Netler" Doyle, an ex-Shamrock Rovers player, they finished the 1935–36 season in a respectable fourth place, behind Bohemians, Dolphin and Cork.

[6][7][4][8] [3][2] There is some evidence to suggest that after leaving the League of Ireland, Reds United may have continued to function as a junior club in some capacity.

Two Shamrock Rovers players active in the mid-1940s, Tommy Godwin[9] and Ossie Nash played junior football with a Reds United.