On 29th January 1793 [his father] Gaetano Fedele Polidori [aged 30] and [his mother] Anna Maria Pierce of Middlesex [aged 19] were married.
On 7th September 1795 John William Polidori was born to Gaetano Fedele Polidori [aged 32] and Anna Maria Pierce of Middlesex [aged 21].
From 1804 to 1810 John William Polidori [aged 8] was a student at Ampleforth College, North Yorkshire.
On 1st August 1815 John William Polidori [aged 19] received his degree as a doctor of medicine from Edinburgh University.
In 1816 John William Polidori [aged 20] became physician to George "Lord Byron" 6th Baron Byron [aged 27] and accompanied him on his trip through Europe.
Around 18th August 1816 George "Lord Byron" 6th Baron Byron [aged 28], Percy Bysshe Shelley [aged 24], his future wife Mary Godwin aka Shelley [aged 18], John William Polidori [aged 20] were staying at the Villa Diodati on the shores of Lake Geneva.
On 24th August 1821 John William Polidori [aged 25] died at his father's house 38 Great Pulteney Street. There were suspicions he had committed suicide by consuming prussic acid although the coroner gave death by natural causes.