At the north-east corner of the northern portion of Great St. Helens. In Bishopsgate Ward Within (P.O. Directory).
In 1162 it is mentioned in a grant of land made by Peter Merewin and Goldeburg his wife to the church of St. Mary of Southwark, the land being "ante ecclam sancte Elene" (Cott. Charter, XXVII. 100).
In 1212, after the Priory of St. Helens was founded, the Church became the Priory Church and was used both as a parish church and for the nuns (S. 173).
It seems to have been rebuilt during the 13th century by Thos. Basing and his brother, William (Ct. H.W. I. 147).
The church is said to have been originally founded by Constantine, and to have been named by him after his mother the Empress, afterwards St. Helen (Cox, p. 4), but there does not seem to be any historical foundation for this statement.
There was a Chapel "Sci Spus" in the church 49 Ed. III. mentioned in will of Adam Francis (Cox, 362).
The living is a Vicarage, and the patronage in early times belonged to the Dean and Chapter of St. Paul's (MSS. D. and C. in Hist. MSS. Com. 9th Rep.), but when the Priory was founded the advowson was given to the Nuns (Dugdale, IV. 553), and remained in their hands (Lib. Cust. I. 236) until the Dissolution, when it passed to the Crown. It now again belongs to the Dean and Chapter of St. Paul's (Newcourt, I. 364).
The double use of the Church by the Nuns and by the parishioners is well illustrated in its structure, as it consists of two parallel naves, 122 feet long, the southern one having been appropriated to the use of the parish, and the northern to the Nuns. Divided by 15th century arcade (Godfrey, 355).
The church was repaired in 1631 and 1633. It was not destroyed in the Great Fire, and the openings into the refectory and cloisters still remain. Restored 1865-8, 1874-6, and in 1891 (St. Paul's Ece. Soc. I. 173).
13th and 14th century windows remain (Godfrey, 355).
The church and parish of St. Martin Outwich were united to St. Helen's in 1873 (Cox, 378).