It's always mentioned how longships gave the vikings an advantage throughout the viking age, but what happened to them? Did they continue to be used after the viking age, or did other styles of ships replace them?
Well, they were sold, broken up, burned, sank, or rotted away. Or in a couple cases were preserved. But I'm assuming that's not what you meant :-)
So the thing to keep in mind is that the longship was one of several types of ship used by the Norse. It survives in popular memory because of ships like the Gokstad ship, but it was used mostly for raiding and in a specific area. It was also made using what's called clinker construction, where the hull is built up from a keel using overlapping strakes of timber sewn together. That makes for a fairly sturdy hull for its size, but one that also uses a lot of wood and is very difficult to make. Around about the 12th century or so, a new construction method started making waves (HA) in northern Europe, called "carvel" construction. Carvel construction is where you fit planks together edge-to-edge over a skeleton of ribs. The advantage to carvel construction is threefold:
it's cheaper than clinker, using less wood for the same size ship;
it's simpler than clinker, using less skilled labor to construct;
it allows for the construction of larger ships carrying more complicated sailing rigs. Clinker-built ships have some inherent disadvantages -- the construction lacks internal framing, so the ship is not rigid enough to carry a large press of sail, and it twists internally in rollers (which the North Atlantic has plenty of). Adding more length or beam exacerbates this issue, so there's an upper limit on the size of clinker-built ships.
Carvel building was tied to the development of the carrack and caravel, first in Genoa then in Spain/Portugal, and later classes of ships that improved on these.
I wrote about some of the changes in naval technology over time in these threads:
http://www.reddit.com/r/AskHistorians/comments/20x9kz/classes_of_vessels_during_the_age_of_sail/
and /u/vampire_seraphin has an excellent answer in this thread, to which I also contributed
If this is useful to you, let me know!
