Silphium was a plant that was a major article of trade in the Mediterranean. It was supposed to have a hot taste like horseradish or garlic. Apicius used it in his recipes. Strabo likened it to asafoetida.

Both the Minoans and Egyptians had specific glyphs for it.

Pausanias, in his Guide to Greece (c.150 AD) mentions it a good deal in conjunction with various legends or myths or even medical usages.

It came out of North Africa, and was the major trade item of Kyrenaika/Cyrenaica/Cyrene, on whose coins it appeared. The valuable part was the resin it gave off, called laser, laserpicium, or lasarpicium, so that the plant was sometimes called laserwort. To the Romans, it was worth its weight in silver, even if it didn't have to come halfway round the world like black pepper.

Various theories exist as to why it may have become extinct around 300-100 BC. It may exist and we just don't recognize it as silphium. It grew along a narrow strip of coast, about 125 by 35 miles (201 by 56 km) is all. Theophrastus claimed it could not be cultivated, which meant it had to be found and maybe encouraged. The climate along the coast dried out, and there was a super-luxury trade in the meat of animals that had grazed on silphium, so grazing and loss of habitat may have killed it off.

In the 1st C, the last stalk of silphium found was presented to the Emperor Nero as a curiousity.