1565 - Robert Wilson became the first minister of the reformed church in Dalkeith;,
1590 - the erection of the wall sealing off the Apse;
1592 - Dalkeith Church established as a parish by Parliament;
1650 - Cromwell’s troops and horses were stabled within the Church building;
1660 -over the next 180 years, lofts were constructed in the Church and were used by the various trades within Dalkeith such as Bakers, Fleshers, Dyers, Weavers, Skinners, Tailors, Shoemakers, Colliers, Hammermen and Gardeners. The Hammermen's Banner is still displayed in the church. See the picture in the Photo Gallery;
1770 - the Apse roof collapses as a result of neglect;
1851 - Church closed for extensive restoration and worship takes place in new West Church;
1854 - St Nicholas Church reopens and West Church becomes a Parish Church;
1879 - Buccleuch Street Church built;
1888 – Present Steeple and vestry erected after the fire of 1885;
1936 – Restoration of the chancel including current pulpit.
2006 - The Apse was leased by the General Trustees of the Church of Scotland to the St Nicholas Apse Trust who took over responsibility for its upkeep.