<p>Sir William's life after 1650 is well covered but for the earlier period there are only a few orders, instructions and isolated documents. The collection includes a log, 1650 to 1651, accounts of battles, 1652 to 1653, a log of the Swiftsure and sailing and fighting instructions, both to and from Penn, for the expedition to the West Indies. The 1665 campaign is covered by an incomplete log of the Royal Charles, a description of the battle of Lowestoft, several sailing and fighting instructions and orders of battle. There are also administrative papers and personal letters covering Penn's tenure of office at the Navy Board.</p>

<p>Part of WYN/10/1 has been published in “Richard Rooth’s Sea Journal of the Western Design, 1654-55,” edited by John F. Battick, in Jamaica Journal V (December 1971). Parts of WYN/10/2 and WYN/18 are published in volume two of Granville Penn's 'Memorials of the Professional Life and Times of Sir William Penn' (1833).</p>

Administrative / biographical background
Penn served under the Commonwealth in the Irish Fleet. He then went to the Mediterranean in the Centurion and Fairfax, 1650 to 1651, before becoming First Captain of the Triumph. During 1652 and 1653 he was Vice-Admiral of the Fleet under General Robert Blake during the First Dutch War. The following year he was appointed General and Commander-in-Chief of the Fleet, in the Swiftsure, for the expedition to capture Hispaniola, returning home in 1655. During the Second Dutch War, Penn was appointed to the Royal Charles, the Duke of York's flagship, in a capacity similar to that of 'Captain of the Fleet'. He served at the Navy Board as a Commissioner between 1660 and 1663, influencing the tactical instructions and drawing up the code long-known as the 'Duke of York's Sailing and Fighting Instructions'. See Granville Penn, 'Memorials of the professional life and times of Sir William Penn. From 1644 to 1670' (London, 1833, 2 vols).