Nordic Merchant Ship (Cog)

Timeline

1. c. 1200–1280Frisia and the Rhine estuary · Low CountriesFrom the late 12th to early 13th century, the cog took shape in Frisia and the Rhine estuary, gradually replacing some traditional Nordic fast ships; its broad flat bottom and high sides were better suited to bulk cargo and sailing over sandbanks and estuaries.
2. c. 1290–1400Lübeck · Schleswig-HolsteinBy the late 13th century the cog had become the mainstay of Hanseatic merchant fleets; regular convoys (such as the Norway route) sailed in cog formations between Bergen, Skåne, and Baltic ports, with standardized hull dimensions easing port handling and insurance pricing.
3. 1400–1450Bremen Kog wreck site · GermanyCog-building techniques matured in the 14th and 15th centuries; wrecks such as the Bremen Kog show rib structure, sternpost rudder installation, and cargo hold layout, providing key evidence for studying the material culture of Hanseatic shipping.
4. c. 1450–1550North Sea and Baltic Sea · Baltic SeaIn the mid-to-late 15th century, larger hulks and carracks gradually replaced cogs in ocean trade, but the cog's sternpost rudder, rib structure, and merchant deck layout continued to deeply influence the development of early modern European sailing ships.