He was born in 1955 in a mountainous region of Kyushu, the southernmost of the main Japanese islands.
His real name is Chizuo Matsumoto and he was the sixth child of a maker of tatami, the rush mat which forms the floor covering of traditional Japanese homes.
A congenital eye defect led to his being educated at a public boarding school for the partially sighted where he took diplomas in alternative therapies such as acupuncture.
Aged 21, he set up a shop selling Chinese medicines in Chiba, the prefecture adjoining Tokyo, but was fined 200,000 yen for selling herbal remedies without a permit, and went bankrupt. In 1984, he set up the predecessor of Aum Shinri Kyo, the "Association of Legendary Hermits with Miraculous Powers", a yoga training organisation that published books on meditation and Eastern religion.
He married and travelled in the Himalayas: it was during this time that he claims to have become enlightened.
In 1989, the renamed Aum Shinri Kyo (Aum Ultimate Truth) was recognised as a religious foundation under Japanese law, entitling it to tax benefits. Early Aum dogma was based around levitation (more like vigorous bouncing in the Lotus position), and meditation practised in yoga centres where many members were recruited.
Mr Asahara's followers were encouraged to show their devotion by donating worldly goods to the cult, which began to buy property in Japan. This was the period of the so-called "Bubble" when rocketing land prices were fuelling an unprecedented expansion of the Japanese economy. From the beginning, Mr Asahara was as effective a businessman as he was a guru.
As the cult grew richer, its teachings changed, becoming harsher and more ambitious. Mr Asahara began to talk about Armageddon, a war between Japan and the United States that would destroy the country between 1997 and 1999.
Again, this was timely, as trade friction and the disillusion of the old Cold War certainties drove a wedge between the two states. Aum's membership swelled quickly, and it began to make enemies.
It was driven out of its Kyushu village base and, in 1989, Mr Asahara and 14 followers made a derided stand for elections to the lower house.
Those setbacks were said to have angered Mr Asahara and it is at this time that he formulated the philosophy of struggle against the state, acquiring cut-price military equipment from Russia, and chemicals - supposedly for making fertilisers and other materials necessary for surviving Armageddon - but apparently for synthesising sarin nerve gas.