On 15 June 1939 the Netherlands issued two stamps to celebrate the 1200th Anniversary of the death of St Willibrord (658-739), only the 5c has a maritime theme.
St Willibrod was an Angle missionary from Northumberland and he was send to the Netherlands from Ireland to do mission work under the Friesian people who were living at the entire North Sea coast from the Scheldt River to the Weser in Germany.
The stamp shows us the landing of Willibrord on the coast near Katwijk, Netherlands at the mouth of the river Oude Rijn in 719 after his passage from England. There are not reliable images of Willibrord, the oldest image of him was made 300 years after his death.
On the left of the stamp is showed a sailing ship in which he made the voyage to Holland, it is a Celtic sailing ship and the ship on the stamp is designed after a medieval seal on the weapon of the University of Winchester, England.
The Celtic ships were flat bottomed with high bow and stern, the hull was made from thick oak planking caulked with moss and fastened to heavy frames by iron nails 2,5 cm in diameter. They had leather sails and anchors with chains and were better suited to the harsh local condition in the northern waters. They could venture inshore through shoal waters and beach safely.
Netherland 1939 5c sg?, scott212.
Source: Internet.