Robert Rich succeeded to an estate consisting of lands in Havering and Romford in Essex, Cholsey in Berkshire, Kensington in Middlesex and Smithfield in the City of London. His younger brother Cope Rich later valued the estate at £8,000 a year, but surviving rentals suggest that half this amount would be nearer the mark.
Despite his family’s strong legacy of involvement in politics and their staunch Presbyterian/parliamentarian traditions, Holland took little interest in Parliament. He seems to have had virtually no contact with Members of the Commons, although his brother-in-law, Sir James Thynne‡, sat for Wiltshire. He did not attend the Convention at all, even though much of its time was devoted to investigating those responsible for his father’s execution. Instead on 30 Mar. 1660 he gave his proxy to another brother-in-law, James Howard, 3rd earl of Suffolk. On 10 May 1661 he again left his proxy with Suffolk and it was probably this proxy which was noted at the call of the House on 20 May.
Sources for studying Holland’s life are extremely poor, but a miscellaneous collection of personal, financial and legal papers survives amongst the records of the court of exchequer. These include household accounts which provide the only evidence available for the existence of three daughters. The documents confirm that by October 1684 his widow had married Richard Bourke, Viscount Dunkellin [I], later 8th earl of Clanricarde [I], but that she continued to be known by the more prestigious title of countess of Warwick.
