Ten letters, 1894-1925, from, to, or relating to the Rev. Dr William Hopkyn Rees, including three, 1912, from the Rev. Dr Timothy Richard, some of which are quoted in H. T. Jacob's biography of W. Hopkyn Rees; with related printed items, 1883-1925; and five letters, 1894-1915, from a Welsh immigrant family in Patagonia.

The series comprises material relating to the Welsh Colonial and General Trading Company Limited, the aim of which was to raise funds to send people to the Welsh Colony in Patagonia. It includes share certificates in the company and letters from D Lloyd Jones, Secretary.