He was born at Higher Bockhampton, now Stinsford, in Dorset, the second son of Robert Jacob and Anne Steldon. The Jacob family were descended from William Jacob, who was living in Tolpuddle in 1450. Robert always valued his association with both towns, and when he applied for a coat of arms he described himself as Robert Jacob of Tolpuddle and Bockhampton. In about 1603 he married Mary Lynch, widow of David ; she was the daughter of William Lynch, a merchant of Southampton. She had one surviving son, William , by her first husband. Mary was a colourful character with a reputation for wit, who once publicly ridiculed the Spanish Ambassador, Count Gondomar. She and Robert has five children, Robert junior, Arthur, Francis, Mary junior and Anne. All of their children were still alive in 1617 when they are mentioned in their grandfather William Lynch's will but only the younger Mary is definitely known to have been still living in 1623. She married Sir James Hamilton of Manor Elieston, a cousin of the Earl of Abercorn.
Solicitor General
Not much is known about his education, nor when he was called to the Bar, or about his early legal career. He was knighted in 1601, and in 1606 he was sent to Ireland as Solicitor General. He was admitted to the King's Inn in 1607 and given chambers there in 1612. Like most successful men at this time he found jobs for his family: his brother Hammett became Clerk of the Peace for Dublin. Robert sat in the Irish House of Commons as one of the two MPs for Carlow in the Parliament of 1613–1615. The 1613 election was notable for the number of disputed results and Robert, who had the usual English settler's prejudice against the Old Irish, wrote that "Irish lawyers did more harm than the priests all combined in opposing the Crown's work" and complained that they were electing "seditious schismatics" as members of Parliament. In fact when all the results were finalised Protestants had a slight majority in the Commons. He was also made a Burgess of Carlow Corporation under the new Royal Charter granted to the town in 1613. He seems to have been a highly competent lawyer, who prosecuted cases regularly before the Court of Castle Chamber and is found giving detailed advice in 1611 on the legal aspects of the forfeiture of the O'Farrell lands in Longford.
Politician
Like his friend Sir John Davies he was as much a politician as a lawyer. He was deeply concerned about the future of English rule in Ireland. After the Flight of the Earls he warned in a famous phrase that "there are 2000 idle men that had no means but to feed on the gentlemen of this country..he was accounted the bravest man that comes attended with most of these followers ". He appears to have thought that the killing of Sir Cahir O'Doherty in 1608 would restore peace; yet the following year he was fearful of the possible return of Hugh O'Neill and the consequences for Ulster: "there are great probabilities that all the people of that province would easily run into rebellion if Tyrone should return, or if any munition or aid should be sent to them from foreign parts". In 1612 he wrote a lengthy memorandum on the weakness of English rule in Ireland, for which he proposed two main remedies: the restoration of a standing army, and the expulsion of the Irish chiefs from troublesome parts of the country, and their replacement by large numbers of settlers. The ordinary Irish people in his view could be left in peace, while loyal Irish chiefs would be required to surrender only a small part of their lands to the Crown.
Death
Jacob's ambition and his undoubted ability ideally suited him to play a leading part in Irish affairs if Sir John Davies was recalled or promoted, but in the event he died in 1618, while Davies was still in office as Irish Attorney General. His widow Mary quickly remarried the well- known politician and poet Christopher Brooke, though she continued to use the title Lady Jacob. She had at least one more child, a son called John, and died in 1622.
Character
Jacob's attitude to the Irish people was stern, but in private life he seems to have been a kindly man. In 1617 he wrote a warm and encouraging latter to his good friend and colleague Sir John Davies about the sad condition of Davies' son Jack, who was deaf and dumb, and generally thought to be mentally deficient: " If your son Jack were now put into the hands of some skilful men, he might be brought to speak. For he is wonderfully mended in his understanding of late, for he understands anything that is spoken to him without making any signs, so as it is certain he hath his hearing". He was apparently fond of theatre, and is believed to have taken part in a masque called Cadmus at Dublin Castle at Christmas 1608.
