Lord Darnley's ideas for his mausoleum were possibly inspired by the Roman remains, including the monumental pyramid mausoleum of Cestius, he saw on the 'Grand Tour'. He may also have been influenced by French artist Nicholas Poussin's picture 'The Sacrament of Ordination'.
Of the detailed instructions he left in his will, it clearly stated that he wanted a square stone building with a 'prominent pyramid' surrounded by a dry moat.
James Wyatt and George Dance the Younger
After the Earl's death, the family commissioned architect James Wyatt to design a mausoleum following the instructions set out in his will.
Wyatt exhibited his design at the Royal Academy in 1783, but due to a heavy workload, the mausoleum was built under the supervision of another famous architect, George Dance the Younger.
Left unused
The mausoleum was completed in 1786, at a cost of £9000 (well over £1 million in today's prices), but there was a problem... For reasons that remain unclear, possibly involving a dispute with the Bishop of Rochester, the Darnley Mausoleum was not consecrated and could not be used for burial.