The club was formed for old boys of St Mark's College, Chelsea, an educational establishment which lasted from 1841 to a merger in 1923, and which is now known as Plymouth Marjon University.

The club first made a mark in the London Senior Cup of 1885–86, beating the strong Casuals side in the third round, and losing to Hotspur (why by now had moved to Wimbledon) in the quarter-finals.

[3] In the same competition, the Saints beat Tottenham Hotspur in the qualifying rounds of 1893–94, by a score of 6–1, in a replay; the match wasj notable for being the first one for which the Spurs issued a programme.

[7] The Saints entered the FA Cup for the first time in 1887–88, beating East Sheen in the first round 7–2 but losing narrowly to the Old Etonians in the second, having twice been ahead.

[11] The club played in chocolate and light blue, which was probably in halves, as that was a popular way to combine those colours at the time.