Siege of Breda (1637) when word came that the Dutch had suddenly invested the city of Breda with a besieging army of 18,000. Breda was the capital city of the baronial fief that had once been the crown jewel in the Dutch estates of the Nassau family in the Habsburg Netherlands before the war started. Frederick Henry had therefore a personal interest in recapturing the city and its surroundings. The siege was preceded by an attempt to surprise the garrison on 21 July 1637 by Dutch cavalry under Henry Casimir I of Nassau-Dietz. However, the gates were closed in time and the Dutch skirmishers
Breda not be plundered, the troops vented their fury upon the inhabitants. In the resulting mayhem, known as "Haultpenne's Fury", over 500 citizens were killed. In March 1590, Breda fell back into the hands of the Dutch and Maurice of Nassau, when a 68 men hand-picked force, concealed under the turf of a peat-boat, had contrived to enter the city in a daring plan devised by Adriaen van Bergen (Siege of Breda (1590)). Around 1610 the construction of the Spanish Gate or "Spandjaardsgat" was started as a remembrance to that successful action. After a ten-month siege in 1624–25, the city again