Sir Alfred James Munnings was born on 8 October 1878 at Mendham Mill, Mendham, Suffolk, across the River Waveney from Harleston in Norfolk. The second of the four sons of the miller John Munnings (1839–1914), Alfred grew up surrounded by the activity of a busy working mill with horses and horse-drawn carts arriving daily. After leaving Framlingham College at the age of fourteen he was apprenticed to a Norwich printer, designing and drawing advertising posters for the next six years, attending the Norwich School of Art in his spare time.

When his apprenticeship ended, he became a full-time painter. The loss of sight in his right eye in an accident in 1898 did not deflect his determination to paint, and in 1899 two of his pictures were shown at the Royal Academy Summer Exhibition. He painted rural scenes, frequently of subjects such as Gypsies and horses. He was associated with the Newlyn School of painters, and while there met Florence Carter-Wood (1888–1914), a young horsewoman and painter.

They married on 19 January 1912, but she tried to kill herself on their honeymoon and did so in 1914. Munnings bought Castle House, Dedham, in 1919, describing it as ‘the house of my dreams’. He used the house and adjoining studio extensively throughout the rest of his career, and it was opened as the Munnings Art Museum in the early 1960s, after Munnings’s death. Munnings remarried in 1920; his second wife was another horsewoman, Violet McBride (née Haines). There were no children from either marriage. Although his second wife encouraged him to accept commissions from society figures, Munnings became best known for his equine painting: he often depicted horses participating in hunting and racing.

Although he volunteered to join the Army, he was assessed as unfit to fight. In 1917, his participation in the war was limited to a civilian job outside Reading, processing tens of thousands of Canadian horses on route to France — and often to death. Later, he was assigned to one of the horse remount depots on the Western Front. Munnings’s talent was employed as a war artist to the Canadian Cavalry Brigade, under the patronage of Max Aitken, in the latter part of the war.

Munnings was elected president of the Royal Academy of Arts in 1944. He was made a Knight Bachelor in July of the same year and was appointed a Knight Commander of the Royal Victorian Order in the 1947 New Year Honours. His presidency is best known for the valedictory speech he gave in 1949, in which he attacked modernism. The broadcast was heard by millions of listeners to BBC radio. An evidently inebriated Munnings claimed that the work of Cézanne, Matisse, and Picasso had corrupted art. He recalled that Winston Churchill had once said to him, “Alfred, if you met Picasso coming down the street would you join with me in kicking his … something something?” to which Munnings said he replied, “Yes Sir, I would”.

Munnings died at Castle House, Dedham, Essex, on 17 July 1959. His ashes were interred at St Paul’s Cathedral, with an epitaph by John Masefield (‘O friend, how very lovely are the things, The English things, you helped us to perceive’). After his death, his widow turned their house in Dedham into a museum of his work. The village pub in Mendham is named after him, as is a street there.