Hercules is another old British bicycle brand that started off well, allegedly producing bicycles strong enough to deserve to bear the name!
With the dominance of Raleigh in the 20th century though, the brand eventually got bought out and it became one of the many brands being made in Raleigh's enormous Nottingham factory, which at the time was the largest bicycle factory in the world.
With the decline of the British bicycle industry though, came the end of Hercules for a while. But through the brand has now been revived by an Indian manufacturer who seem to have applied it to a highly customizable mountain bike.
Taken from: http://www.bsahercules.com/cycle-customiser.asp