Late on the night of 4 December 1925, students of the Leidsch Studenten Corps started a rugby club in Leiden. They made arrangements, formed a first board, and ended the evening in songs and speeches.
In the weeks after they got shirts, used the changing rooms at rowing club Njord, and laid a pitch. When they had trained enough they invited Haarlemse Rugby Club and won 20-5. The Corps Collegium then recognised them.
Rugby among Leiden students later died out. That 1925 side is prehistory, not this club’s founding. LSRG history page
A Minerva alumni magazine says Leiden students were invited to a Delft student-club sevens in late 1959 and won it. A few months later they arranged a return, bought old football shirts, found new players, and on 14 October 1960 L.S.R.G. was a fact. Virtus Nitor, winter 2010
On 14 October 1960 L.S.R.G. was founded as a society of the Leidsch Studenten Corps, in much the same way as 1925.
Sky blue came from Koninklijke Studenten Roeivereniging Njord. Maroon came from the Minerva society. In the 1960s and early 1970s a full year of competitive rowing was one of the conditions of playing for L.S.R.G. LSRG history page
The Rugby Nederland club page gives the colours as white and blue. This page leaves both accounts. Rugby Nederland club page
On 28 March 1971 Rugbyclub DIOK was founded with the backing of L.S.R.G. DIOK history page
After the 2000/2001 season the incoming board faced a club that might fold. It had about fourteen members. Half had decided to stop or move to Ereklasse clubs; they had graduated. There was no coach, a leftover Minerva debt from the 1980s of about two thousand guilders, and nothing in the club account.
The board chose to rebuild: bring old boys back for advice, money and players, open the club to anyone who wanted to play, and treat graduation as not the end. On 19 March 2010 the Stichting beheer Leidsch Studenten Rugby Gezelschap 1960 was founded to keep that recovery in place. LSRG old-boys foundation