The Club was born in 1919 when a group of young men, old friends and school friends were having coffee together in 'Bunty's Tea Room' in the High Street on the corner of Vaughan Road, now alas no longer existing as a tea room - it is now occupied by 'Cancer Research UK'. For the most part they had all played rugby at school and decided they would try and form a side to continue playing together.

After some difficulty they found a ground they could use in Rothampstead Park, a large open area owned by the Lord of the Manor, contacted some opponents and managed to arrange a few games during the 1919/20 season, playing as Harpenden Old Public Schoolboys. The following season, on 2nd March 1921, they were officially constituted as the Harpenden Rugby Football Club and began to establish themselves. Unfortunately their use of the pitch in Rothampstead Park was abruptly terminated by the then Lady of the Manor who apparently classified rugby players as 'rough loiterers'; a new pitch was then found in Townsend Lane.

At the same time the changing accommodation, a barn behind 'The Cock' Public House in the High Street (now 'The Old Cock Inn') was transferred to another barn behind the rival pub on the opposite side of the road, 'The Cross Keys'. That Pub has remained a meeting point for Club Members over the years.

It was, under Reg Johnson (the Landlord at that time), instrumental in establishing The National Original Cross Keys Pub Sevens which over 30 years has grown from a small ad hoc tournament catering for a few local players who wanted to play on a Sunday to the annual HRFC Pub Sevens.

By 1926 the Club was able to establish a more permanent home in a field behind the water tower in Overstone Road, with a wooden hut as both pavilion and changing room. Additional land was subsequently acquired, affording another pitch, and a spectators' stand was built at that time. The Club was flourishing, having 65 playing members. Nearly all of them found their way into the services during the last war when the Club had to cease playing. In 1946 play began again at Overstone Road thanks to the forethought of the founders who had, at the outset, formed a limited company, which assisted in restarting the game after the cessation of hostilities. Rugby prospered in the town.

In 1948 the Dalkeith Club was formed to provide small social amenities including a licensed bar; and to accommodate it in 1951 a further hut was built. In 1955 the hut was doubled in size. By then the Club was regularly fielding 6 XVs. Having only 2 pitches and limited changing and bar facilities, and no room to expand, the need for completely new accommodation became obvious.