Roy Precious - Antiques & Fine Art has dated this piece to the 1880s.
This is a fine military portrait by an artist as yet unknown, although the influence of Sir Francis Grant P.R.A. can be seen.

Captain St.John Mildmay wears dress uniform, which is still worn by The Royal Horse Artillery on state occasions.
CHARLES BEAGUE ST.JOHN MILDMAY (1861-1923) was the oldest surviving son of Arthur George St.John Mildmay (1824-1883) and his wife Charlotte (nee Beague).

The St.John, Mildmay and Beague families were all old ones, with a history of service to the country...military and political.
Charles married a kinswoman, Evelyn Augusta St.John Mildmay in 1892. She was the daughter of Capt. Edmund Henry St.John Mildmay, late of the 5th Radetzky Hussars in the Austrian Imperial Service; he became Equerry to H.R.H. the Duke of Cambridge.

Charles and Evelyn had two daughters, Dorothy and Letitia.
Charles served with the Royal Artillery, the Royal Horse Artillery and the 4th Bttn. of the Somerset Light Infantry. He saw service in the Boer War 1900-01, becoming a major (Hon) in 1908, presumably upon his retirement.

The photographs (see Image 4) show him wearing a campaign medal, probably from the Boer War.
Also in Image 4 can be seen his sword; an 1821 pattern Artillery officers sword by Wilkinson of Pall Mall, London.
Numbered 23530, the sword was made c.1880 which would have been when Mildmay was a lieutenant.
The blade bears the Royal Coat of Arms for Queen Victoria over the Royal Artillery motto 'Ubique'. On the other side there are winged thunderbolts, Royal Artillery, scrolling foliage and two heraldic crests...the lion of Mildmay and the falcon of St. John.
It is often forgotten that officers of the artillery were 'front line' troops through the Victorian period, as the science of indirect fire (engaging targets out of direct line of sight) was only really developed in World War I. Thus an officer's sword was far more than a dress piece, and could on occasion be called upon to save his life.
SIZE: 64 x 42 inches inc. frame.
PROVENANCE: by descent in the St.John Mildmay family formerly of Hollam House, Dulverton, Somerset. The St.John Mildmays owned Hollam for hundreds of years, Sir Walter St.John Mildmay was the last to live there in the 1990s. (Image 5)
Roy Precious - Antiques & Fine Art has dated this piece to the 1880s.
Roy and nadine precious: specialists in portraiture from the 16th to the 20th century. Established in 1972.
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