A framed painting by Jack Butler Yeats entitled "Born of Pain".

John "Jack" Butler Yeats (29 August 1871 to 28 March 1957) was an Irish artist. Yeats was born in London, England. He was the youngest son of Irish portraitist John Butler Yeats, and the brother of the Nobel Prize winning poet William Butler Yeats. His favourite subjects included the Irish landscape, horses, circus and travelling players. His early paintings and drawings are distinguished by an energetic simplicity of line and colour, his later paintings by an extremely vigorous and experimental treatment of often thickly applied paint. He frequently abandoned the brush altogether, applying paint in a variety of different ways, and was deeply interested in the expressive power of colour. Despite his position as the most important Irish artist of the 20th century (and the first to sell for over £1m), he took no pupils and allowed no one to watch him work, so he remains a unique figure.