[1] De Jong was born in Mannar, Sri Lanka as the son of Jacob de Jong Senior, from Veere and in 1722 Commandeur of Jaffna, and Johanna Pasque de Chavonnes, from Hulst.
He worked his way up in the Dutch East India Company.
He served as special commissioner at the pearl fishery in 1722 and as Dutch Ambassador to the Court of Kandy in 1736.
He was married four times, after his first wife, Elizabeth Mooyaart, died in Galle in October 1747.
[2] His fourth wife, Cornelia Schokman, remarried as a widow in 1765.