He later worked at Celynnen and Abercarn collieries He soon involved himself in trade union activities and politics and in 1890 was elected the local agent for the Monmouthshire Miners' Association.

[1] Brace was an early advocate of a single union for all of Britain's colliers, an issue in which he clashed with William Abraham (Mabon).

He continued taking the Liberal whip for some years, despite the Miners' Federation of Great Britain, which sponsored him, having affiliated to the Labour Party in 1909.

Brace was criticised over his failure to support the "Datum Line" strike while he was equally critical of the "wild" union leaders who were determined to bring about conflict in the coalfields.

The younger son, Ivor Llewellyn Brace, became Chief Justice of the Supreme Court of Sarawak, North Borneo and Brunei.