Accounts of Christopher Wren's early years are usually derived from the partial and inaccurate family history, Parentalia (1750). They are here reinterpreted in the light of recent research, including investigations of his family background, and of the mass of recent scholarship on the intellectual life of Civil War and Interregnum Oxford. College and University administrative records are also used. Born in 1632, Wren's childhood as the only boy in the large family of Christopher Wren, Dean of Windsor, is considered. He appears to have spent the First Civil War being privately tutored in his family in royalist-occupied Wiltshire, not, as usually asserted, at Westminster School, separated from his family; he attended Westminster only briefly, probably in 1645-6 after the Parliamentary occupation of Wiltshire and his father's imprisonment. His father and Christopher's brother-in-law, William Holder, were major intellectual influences. From 1646 he resided with Charles Scarborough, eminent physician and mathematician; there he encountered the group of natural philosophers which included former Parliamentarians and ex-royalists, notably from William Harvey's Oxford circle. John Wilkins, one of the former, intruded as Warden of Wadham College, Oxford, by the Parliamentary Commissioners in 1648, recruited Wren as a ‘fellow-commoner’ (privileged student). College records reveal Wren as something of an administrative anomaly; he was probably the intellectual companion of the Warden rather than a normal undergraduate student. He frequented the meetings of natural philosophers which Wilkins helped to animate. He showed a precocious talent in pure and applied mathematics, in astronomy, allied with an enthusiasm for scientific instruments. His various seniors took every opportunity to advance his career by bringing him to the attention of the influential, including Oliver Cromwell. His election to a fellowship of All Souls College, and his appointment to the chair of astronomy at Gresham College, London, is interpreted in this light. Detailed consideration ends with Wren's inaugural lecture at Gresham in 1657. However, administrative records are again used to examine the evidence for Wren's residence in Oxford (about one term in each year) during his time as Savilian Professor of Astronomy, 1661-9, when he turned his attention to architecture, and the possibility of constructing his itinerary for those years is considered. Wren's youth saw him massively exposed to serious intellectual adult society marked by a keen interest in mathematics and natural phenomena, although comprising various schools of political and religious thought; the possible affect of these milieus on his personality is tentatively explored, even while recognising that this may not represent the whole picture. Nevertheless Wren's intellectual seriousness and notable self-discipline, and his aversion to demonstrative enthusiasm, may well reflect the experience of his formative years.