History of the oboe

A shawm

The oboe is a direct descendant of the shawm and the hautboy.  A shawm is a six-holed instrument with no keys that produces a very powerful, raucous sound.  It's often associated with ceremonial music and processionals.  During the mid-17th century the shawm became the hautboy, which has eight holes and a completely exposed reed, allowing for greater control, a softer timbre, and greater difficulty to play.

Further changes were made to the hautboy between the 17th and 19th centuries.  (The instrument also found a place in orchestra during this time.)  Over time, it was given a narrower bore, thinner walls, and smaller finger holes.  While this increased agility and produced a quieter, more focused tone, the lack of keys meant it still had inaccessible or different-sounding pitches.  Therefore, the Conservatoire system was introduced in the 1870s.  The speaker key was added, and the instruments became primarily made of African blackwood.

Other members of the oboe family include the oboe d'amore (a "mezzo-soprano" oboe), oboe da caccia (a "tenor oboe"), and cor anglais (more commonly known as the English horn.)  The oboe de caccia has faded away, but the English horn continues to be popular.  It's plays a perfect fifth below the oboe, is slightly longer, and has a round bell.  It's compass is the same as the oboe's: b♭ to f#'''.

The oboe's and English horn's compasses