Dutch Captain: Jan Adriaanszoon van Dieman

Captain Jan Adriaanszoon van Dieman served the Admiralty of Rotterdam (the Maze). In 1628 and 1629, he commanded a small jacht of 60 lasts armed with 8 guns. In 1636, he commanded the ship Prins Hendrik, vessel of 200 lasts. A ship of 200 lasts might be as large as 124ft x 29ft x 12ft. The Prins Hendrik was completed in 1629. Her crew consisted of 90 sailors and 20 soldiers. The Prins Hendrik carried 24 guns, consisting of 10 bronze and 14 iron guns. He left the Goeree Gatt on April 29, 1639, incompany with Tromp in the Aemilia. Vice-Admiral de With was lying off the Meuse with captains Coulster, Vijch, Brederode, Voornham, Keert de Koe, Halffhoorn, and Ringelssen. Tromp and Captain van Dieman headed to join the others. At the Battle of the Downs, Jan van Dieman was in Lt-Admiral Tromp's squadron. Sources:

1. James C. Bender, unpublished manuscript "Dutch Ships 1600-1700", 2005.
2. Dr. M.G. De Boer, Tromp en de Armada van 1639, 1941.
3. Charles R. Boxer, The Journal of Maarten Harpertszoon Tromp Anno 1639, 1930.
4. Dr. F. Graefe, De Kapiteinsjaren van Maerten Harpertszoon Tromp, 1938.