In August of 1600 he sailed as part of a fleet of ships that was commanded by the Vice-Admiral Anton of Burgundy, Lord of Wacken. The fleet was comprised of six vessels of the royal Spanish privateer fleet and six private privateers. Jacobsen was one of the latter six. He had a ship of 70 tuns which carried 12 cannon and had a crew of 77.
On the night of 9/10 August the fleet took sail from Duinkerken. On August 14 the met with the Dutch fleet of fishing-boats near the Scottish coast that were protected by 4 warships. These were immediately attacked. The vessel Den dolphijn of captain Willem Dirkszoon Cloyer exploded when a cannon-ball struck its gunpowder-room. The other three warships were chased away and the fishing-boats were then an easy prey for the privateers. Moreso because some of the vessels carried fishermen that were Mennonites (weapons and violence were against their belief). The privateers treated the crews of captured vessels very harsh in retribution for the harsh treatment which captured Spanish privateers received in the Netherlands. In Historien by Van Meteren, written in 1661, he describes some of the typical actions against fishermen:
"Dese Duynkercksche schepen namen veel visschers, eenighe verbranden sy, andere soncken se, ende de arme visschers naghelden sy onder in de schepen, boorden gaten in de schepen, en lieten se allenskens sincken. Oock waeren twee schippers die niet onder in 't schip en wilden gaen, om alsoo versmoordt te worden. Dies namen sy dese, en naghelden die dwers cruyswyse d' een over den anderen, met naghelen door handen en voeten, ende lieten se alsoo sincken." |
In 1602 Jacobsen sailed from Duinkerken again together with two other privateers. Of the three royal Spanish privateers the two vessels of Willem Janssen and Michiel Jacobsen managed to sail away without being noticed by the 17 Dutch warships that tried to form a blockade around the port of Duinkerken.