Married to miniature painter Rosalie M. Emslie, they had a daughter, Rosalie Emslie, who became a figure, portrait and landscape painter. Emslie turned increasingly to portraiture later in life. He had a great passion for the Orient, and spent three months exploring Japan.
Emslie exhibited in London at the Royal Academy between 1869 and 1897.
Between 1897 and 1901, he painted a series of pictures illustrative of the theme "God is Love". Nine large oil paintings from this series were exhibited at Towneley Hall in Burnley, Lancashire from May 1904 until April 1905.
Also at the Royal Birmingham Society of Artists, Glasgow Institute of the Fine Arts, The Royal Scottish Society of Painters in Watercolour, Leicester Gallery, Walker Art Gallery in Liverpool and Manchester City Art Gallery.
He was an elected an associate of the Royal Society of Painters in Water Colours in 1888 and a member of the Royal Society of Portrait Painters in 1892.