Linfield House-front view (Michael Dwyer 1987)
The earliest references to the Apjohn family in Ireland is found 1) in County Derry between 1658 and 1682 where two Apjohns, both Curriers, and their families lived, 2) in Limerick where John Apjohn, a Soldier, died in 1655, and 3) in Dromkeen in the Parish of Grean where Thomas Apjohn lived as early as 1641. Little is known of the first two, but Thomas is the pater familias of the Apjohn family in County Limerick.

Thomas Apjohn, as we shall see, had two sons-Michael and William. As in most families of the period, children were named after parents and brothers and sisters; as a result, there are a plethora of Apjohns named Thomas, William and Michael and in some cases it is difficult to determine which individual is referenced in a specific event such as memorial, will, marriage, birth, etc.