The black stuff that is used in pencils is graphite.
Graphite is actually pure carbon. It is like top quality coal.
Some time after the year 1500 a huge amount of pure graphite was discovered in the north of England. The local people realised that this graphite was very special stuff.
At first graphite sticks were found to be very good for marking sheep, but soon they were also used for writing on paper. To stop the fingers from getting black the graphite sticks were wrapped in string, or even sheepskin.
News of these early pencils spread fast, attracting artists from all over the world.