Of medieval origin, it was destroyed by the Great Fire of London, and rebuilt to the designs of Sir Christopher Wren.

The only record of her death is in the Exchequer documents of 1413: "for expenses and other charges incurred for the burial of the wife of Edmund Mortimer and her daughters, buried within St Swithin's Church London ...

[5] The church was rebuilt at the expense of Sir John Hind in 1420, renovated in 1607–1608, and again, shortly before the Great Fire, at a cost of £1,000.

[1] Destroyed in the Great Fire of London in 1666, the church was rebuilt to a design by Sir Christopher Wren in 1678[6] at a cost of £4,687 4s 6d.

[3] The south, east and west fronts each had three windows, with an elliptical pediment over the central one; the pediment on the south front, towards Cannon Street, was decorated with a carved wreath, flanked by festoons in high relief, while the heads of the flanking windows were decorated with festoons of drapery.

Most of the church, however, was covered by an octagonal dome, springing from seven half-columns against the walls, and from one complete column in front of the north gallery.

The pews, which had formerly faced south, were cut down and turned towards the east, galleries were removed, the pulpit was lowered and its sounding board taken away, and a brass chandelier that had hung from the centre of the dome taken down.

This structure, presumably the rebuilding of 1420, replaced an earlier church of which few traces remained; these suggested it had been a simple building with a nave and a single aisle, dating to the 12th century.

[14] A medieval grave slab of Purbeck marble was found reused in the foundations of the Wren church.

The inscription revealed that it had covered the heart-burial of Joanna, wife of Fulke de St Edmond who had been one of the sheriffs of the City of London in 1289–1290.