Loans to the king as well as fines to the parliament had greatly injured the Isham estates, when in 1651, Sir Justinian succeeded to the Isham baronetcy.
Justinian Isham IV was born on 8 July 1740, probably at Oxford, to Euseby Isham, the Vice-Chancellor of Oxford University and his wife Elizabeth (Mary) Panting.
Sir | Sir Walter Scott | Justinian I | Sir Arthur Conan Doyle | Sir Robert Peel | Sir Arthur Harris, 1st Baronet | Sir Raylton Dixon | Sir Harold Hillier Gardens | Sir Fitzroy Maclean, 1st Baronet | Sir Francis Baring, 1st Baronet | Sir William Temple, 1st Baronet | Mark Isham | Sir Richard Fanshawe, 1st Baronet | Sir William Johnson, 1st Baronet | Sir Robert Eden, 1st Baronet, of Maryland | Sir Orlando Bridgeman, 1st Baronet, of Great Lever | Sir Nigel | Sir John D'Oyly, 1st Baronet, of Kandy | Sir James Fergusson, 6th Baronet | Sir Henry Rawlinson, 1st Baronet | Sir Henry Rawlinson | Sir Frederick Pollock, 3rd Baronet | Sir Douglas Quintet | Sir Charles Trevelyan, 1st Baronet | To Sir, with Love | Sir William Williams, 1st Baronet, of Kars | Sir William Johnson | Sir Jonathan Trelawny, 3rd Baronet | Sir John Moore | Sir John Gell, 1st Baronet |
In the next year he was following the lines of Torricelli and Robert Boyle; and, dedicating the resulting work to Sir Justinian Isham, he brought it out in 1662 as Tractatus de Restitutione Corporum, which replied to Francis Line.
He died on 15 December 1772, and was succeeded as baronet by his nephew Justian Isham, the son of his younger brother, the Reverend Euseby Isham.