Career
He joined the civil service of the East India Company in 1752, as a factor, and rose through a succession of positions. He purchased the Wilton Park Estate in Buckinghamshire from the Basil family, in 1760, or around 1770. Du Pre was Governor of Madras from 1770 to 1773.
He was mostly preoccupied with the construction of fortifications there.
His authority was circumscribed: Eyre Coote, the military commander, and Sir John Lindsay who had overall command in the East Indies, left him little room in which to operate. Du Pre at the end of his life became a Fellow of the Royal Society, owing the honour to his appointment two decades earlier of Alexander Dalrymple as his deputy.
He died at Beaconsfield. Of the children of Josias and Rebecca:
Eliza married Colonel Brice, and then Review
John Blackwood, son of Sir John Blackwood, 2nd Baronet.
