Edmund Denison, the son of Lord Grimthorpe was born at Carlton Hall, near Newark in 1816. After being educated at Eton and Trinity College, Cambridge, he became a lawyer.
In 1845 Denison was appointed parliamentary counsel for the Great Northern Railway (GNR). Denison’s family were closely associated with the GNR. He father, Lord Grimthorpe, was chairman (1847-64), and his brothers, Christopher and William, were both directors of the company.