[1] In February 1876, he took part in trials organised by the Druids' founder, Llewelyn Kenrick, to select Welsh players to represent their country in a match against Scotland.
[5] A week later, on 30 March 1878, Druids played in the final of the inaugural Welsh Cup tournament, losing 1–0 to local rivals Wrexham.
[6] Known as "little Billy", Williams became a stalwart of the Druids side, who "could run all day" and "had endless reserves of stamina", although "never a subtle player"; his strong points were his "perfect tackling" and his "vigorous support" of the forwards.
[1] In a report on one match, it was said that "he puts a stop to many a dangerous run, he is a most effective player though not one of the fastest.
[1] Williams made eleven appearances for Wales in official international matches, as follows:[7] Druids