The Club was not granted Welsh Rugby Union status until 1919, immediately after World War I.
Between the Wars the club competed in the local cup and league competitions. In 1922-23 the club were the K.O Cup Winners whilst in 1935-36 it repeated this feat in becoming the West of Llanelly K.O. Cup Winners.
After the Second World War, the club resumed its activities and in 1947-48 under the captaincy of Chris Leonard, became the Pembrokeshire and District League K.O. Champions.
This feat was repeated in 1960-61 under the captaincy of Derek Hayward. Unfortunately this is the last occasion on which the K.O. Cup has come to Crickmarren.
1954-55 was probably one of the most successful in the club's history under the vigorous captaincy of John Shanklin the team were both the Pembrokeshire and District League Champions and runners up in the K.O. Cup tournament.
This period in the clubs history also saw the club win the county 7-a-side tournament on several occasions.