Born in Hackney, London, and baptised at St John, Hackney, on 27 September 1826, Dudley was the child of a well-to-do family. His father, Charles Stokes Dudley of Clonmel, County Tipperary, an Irish provision merchant, writer and philanthropist, was noted on Robert’s baptismal record (and also on his marriage certificate) as “Gentleman”. Charles’s wife was Sarah Dudley, née Haycock, and they had thirteen children in all. [family tree listing at Geni]

On 4 August 1859 at age 32, Robert Dudley was married in Liverpool to Amelia (Amy) Hunt, aged 26. Amelia’s father Andrew Lucas Hunt was also an artist [Marriage register], as was her brother Alfred William Hunt. In 1857 Alfred had given Robert a watercolour of a coastal scene inscribed “To R. Dudley from A.W. Hunt” [Auction record], and this perhaps indicates Dudley’s interest in the sea, which was to be the subject of so many of his paintings from the 1860s into the 1890s. On the 1861 census Dudley is listed as “Artist in Painting”.

After their marriage, the Dudleys lived at 32 Sussex Place, Kensington, London, where they had two children: Guildford, born 1860, and Robert Ambrose, born circa 1867. A letter to Henry Clifford dated April 1868 has the Kensington address, but by the time of the 1871 census the family had moved to 31 Lansdowne Road in Notting Hill, where Dudley lived until his death on 28 April 1909