The first bryophyte specimens were donated to National Museum Wales in 1913, soon after the formation by Royal Charter (Harrison 1982). Subsequent donations were few until the museum relocated to its present site in Cathays Park, Cardiff in 1919. The move necessitated the appointment of Assistant Keeper, A.E. Wade, a bryologist whose inaugural accomplishment was the establishment of a lower plant herbarium. The appointment instigated a rapid expansion of the collection with a series of purchases of important personal collections, including those of D.A. Jones in 1920 and J.A. Wheldon in 1925. A.E. Wade was employed by the museum for 42 years and during this period, 43,000 bryophyte specimens were added to the collection.
The appointment of A.R. Perry as the Museum's bryologist in 1971 marked a further period of expansion for the herbarium. During his time here 168,000 specimens were added, including important collections such as those of P.W. Richards, F. Rose, E.C. Wallace and R.D. & J.W. Fitzgerald. A.R. Perry also donated his personal collection of 10,000 specimens in 1996. In 2000, R. Tangney1 was appointed Head of Cryptogamic Botany and Bryophyte Curator.
Since then, the herbarium has continued to expand. Two important bryological collections entered National Museum Wales in 2001. Since 1970, the British Bryological Society's UK collection (BBSUK) had been housed in the Museum, and in 2001, the collection was officially donated. This collection contains approximately 29,000 specimens of British bryophytes, predominantly made up of voucher material for new vice-county records.
Also in 2001, the H.L.K. Whitehouse collection was donated to the museum. This collection includes some 10,000 bryophyte specimens and a unique collection of stereoscopic photographic slides that covers approximately 80% of the British bryophyte flora and almost all of the British Sphagnum taxa. The best stereoscopic slides of the British Bryological Society were scanned by J. Sleath, to represent as many species as possible. These stereoscopic images can be viewed here.
Today, the Herbarium provides comprehensive coverage of the British bryophyte flora, in terms of the taxa represented and their distribution. Noteworthy worldwide exsiccatae further enhance the breadth of the herbarium, bringing the percentage of foreign specimens in the herbarium to a significant 30%. Altogether, this comprises an internationally important collection in terms of scope and quality.