Robert Thomas was a Welsh newspaper proprietor, printer and early settler of South Australia who was born on a farm 'Rhantregynwen', at Llanymynech, Powys, Wales.

Proclamation Day commonly refers to the anniversary of the proclamation of government of the province of South Australia, which continues to be celebrated in South Australia on 28 December, although no longer a public holiday. The anniversary of the establishment of self-government on 21 October 1890 was formerly known as Proclamation Day in Western Australia.