Rooibos is not technically a tea as it not made from the "Camelia Sinensis" plant, but it is herbal and does not contain caffeine.
The story of Rooibos starts at the turn of the century in South Africa. The locals first discovered the fine needle like leaves of the wild "Aspalathus Linearis" plant made for a tasty aromatic tea. The first plants were harvested, chopped and bruised with hammers leaving them to ferment before drying in the sun.
Today seeds are planted and tended to for 18 months before harvesting. Cut Rooibos is bruised between rollers and left to ferment and the dried.