It was built by the Saxons in about 1000AD on the site of a Roman building, from the time when Colchester was capital of the province of Britain (a position it held until Boudicca burned it down). It was completely rebuilt in ther 1300s, and then rebuilt and extended in 1875-1876 by Sir George Gilbert Scott, who was the architect of many churches along with the Albert Memorial and the Midland Grand Hotel at St Pancras station in London. This is when the enormous spire was added.
Attendance dropped off in the 1950s, and the church was demolished in 1955. The land was bought by the Co-Operative Society, which built a department store on the site. The Co-Op ran into money problems in the 2000s, and in 2010 closed the store and several others in Essex. St Nicholas House has now broken up into units, but the original façade remains. In the 1950s, you could demolish thousand-year-old churches with impunity, but in the 2010s you had to keep the exterior appearance of fifty-year-old buildings.
This stone plaque therefore remains on the side of the building, as it was when the Co-Operative Society built the structure:
If they couldn't spell "labour" properly, the store was doomed to fail.