It is dedicated to Cyprian, a third-century martyr and bishop of Carthage and is near the Clarence Gate Gardens entrance to Regent's Park, off Baker Street.

Gutch eventually negotiated one tenth of St Paul's parish be transferred to a new mission district where church attendance was in any case poor and which was then densely populated due to the overcrowded slums.

Gutch proposed to dedicate the mission chapel to St Cyprian of Carthage, explaining:[2] "I was especially struck by his tender loving care for his people, the considerateness with which he treated them... And I said, 'If only I can copy him, and in my poor way do as he did, I too may be able to keep my little flock in the right path, the road which leads to God and Heaven'.

A surpliced choir was an unusual sight in the ‘60s, except in cathedrals and special advanced churches, and the daily celebration, which was carried on in this little sanctuary for 36 years, was something still more strange.

[3] Over the next thirty years St Cyprian Mission Chapel flourished, but holding only 180, multiple Sunday services were needed to accommodate demand.

The new St Cyprian's was completed with almost a year to spare, and was dedicated to the Glory of God and the memory of Charles Gutch by the new Bishop of London, Arthur Winnington-Ingram.

[2] The sale coincided with the clearance of run-down houses in Park Street – today Glentworth Sreet – when the arrival of the Great Central Railway terminus at Marylebone station and its adjacent fashionable hotel was altering the desirability of the neighbourhood.

[2] At present the organ's decorative case in the west gallery still remains incomplete, as do minor elements of carved stone ornament.

Commissioned in 1899, it was constructed between 1901 and 1903, the first new church completed to Comper's designs (his previous work comprised restoration and embellishment of existing buildings).

[5] St Cyprian's was designed to reflect Comper's emphasis on the Eucharist and the influence on him of the Oxford Movement; he said his church was to resemble "a lantern, and the altar is the flame within it".

[6] Therefore, the interior features unadorned whitened walls in the nave, to emphasise the contrasting richness of painted and gilded furnishings in the sanctuary.

Writing a year after its consecration, and in spite of the still incomplete decoration of the interior, T. Francis Bumpus wrote "Mr. Comper's researches into the history of our old English Uses have enabled him ... to produce one of the most beautiful, harmonious and correctly arranged churches that has been built in London for a long time.

[5] Architectural journalist Ian Nairn was another advocate for St Cyprian's: "Quiet and reserved outside; but the most joyful church interior in London.

Tall white arcades, clear glass to let the light stream in across the polished wood floor, uncluttered by pews to Comper's lacy gilded rood screen.

[18] Nikolaus Pevsner saw late Gothic-revival architecture as old-fashioned and generally gave it little credit; but he praised Comper's work at St Cyprian's, albeit a little grudgingly: "If there must be medieval imitation in the twentieth century, it is here unquestionably done with joy and care.

[20] Anthony Symondson wrote that St Cyprian's established Comper's "primacy as the most influential English church architect of his generation.