The painting shows an event during the war between Sweden and Denmark, when Dutch merchant ships trading in the Baltic had to be escorted by men-of-war. On 9 June 1645, 300 merchant ships set sail under the command and escort of Witte de With, Vice-Admiral of Holland and Westfriesland. The shore of Vlieland, looking across to Terschelling, is shown on the left with a large crowd of people watching the departure. Instead of detailing the departing fleet, the artist has concentrated on the smaller vessels and on the relationship between the watching people to the ships as they are leaving.

Prominent in the left foreground is a ship's barge, with an ensign and a coat-of-arms and lion supporters, bringing an affluent couple ashore just by a little inlet. Beyond this is a kaag together with a small fishing boat known as a weyschuit. Another kaag is partly visible together with a ship's barge nearby. To the left up the shore is a boeier yacht surrounded by a group of men and women, and to the left is a cart drawn by two horses. In the left middle distance, with dunes behind, stands a beacon surmounted by a rectangular basket, used as a leading mark. In the middle distance, right, is the 'Zon', identifiable by a sunburst on her tafferel and next to her on the right is a ship with Pegasus, the winged horse, on the stern. Men-of-war can be seen sailing away in the distance. In the right foreground is a galjoot, in port-bow view, lying head to wind with her gaff mainsail brailed up and her foresail lowered. A small boat is leaving her starboard side.De With's flagship, 'Brederode', is on the extreme right and is partly hidden by the galjoot, with various ships ahead of her. The mainsail is ready to be hoisted. She flies the common Dutch flag at the main and as an ensign. Ahead of her are two ships, one flying a rear-admiral's flag and with two people riding on a whale on her tafferel. The main fleet of merchant ships is in the right distance. The fleet is away on the right. The picture has probably been cut down on the right and is one of several different versions of this subject by the artist.

Born in Leiden , van de Velde moved to Amsterdam with his two sons Adriaen and Willem, who were also painters. The former and younger painted landscapes but with Willem, the older son, he formed a working partnership specializing in marine subjects which lasted to his own death. Willem the elder was primarily a draughtsman who spent his career drawing ships and is believed to be one of the earliest artists to accompany fleets into action to record these events. He did this officially with the Dutch fleet from 1653. The resultant works, known as grisaille drawings or more accurately as pen-paintings ('penschilderingen'), were done in pen and ink on prepared lead-white panels or canvases. This technique enabled van de Velde's work to be full of detail and show his knowledge of shipping. He originally applied a cross-hatching technique to show darkness and shadow but from the 1650s increasingly used a brush to indicate shadow, clouds or waves. Van de Velde was the leading Dutch master in marine grisailles but also produced a handful of oils towards the end of his life. He briefly visited England twice, in 1661 and 1662, but by 1673 had moved there permanently with Willem the younger. Both worked for Charles II and his brother James, Duke of York, and they became the founders of the English school of marine painting. A great deal is known about him thanks to a list of his depictions of naval battles compiled in January 1678 by Captain Christopher Gunman. The picture is signed 'W V Velde' twice, bottom left.