Adi Shankaracharya (~800 CE) was the son of a Nambudiri-Brahman in Kerala, who consolidated the doctrine of Advaita Vedanta. He travelled across India to propagate his philosophy through discourses and debates. His main work was the Brahma Sutra Bhasya, a commentary to the Brahma-Sutras.
Adi Shankaracharya established the importance of monastic life as mentioned in the Upanishads and in the Brahma Sutras, in a time when the Mīmāṃsā school established strict ritualism and ridiculed monasticism. He founded four mathas (monasteries), which helped in the revival and spreading of Advaita Vedanta. He is believed to be the organiser of the Dashanami monastic order and unified the Shanmata tradition of worship (Shiva, Vishnu, Shakti, Ganesha, Surya and Skanda as One). (The seven Dasanami Akhadas are Juna, Niranjani, Mahanirvani, Ananda, Atal, Avahan, Agni with their own leaders.)
🕸 Maharishi Mahesh Yogo was the secretary and a sadhu but not an accepted disciple of Guru Dev Brahmanada Saraswati. Maharishi disappeared soon after Gurudev's death and reappeared 2 years later - he had no official order of guru dev for a mission, and his teachings are completely different.
👳 The momentary 'Shankaracharya' Vasudevanand Saraswati (since 1989) didnt have the necessary qualifications. He was not a Sanyasi before 1989 but a teacher in a government-aided school and drew salary till November 13, 1989.
Since 1989 he has been litigating in Allahabad (where his falsified submitted assessment was proven) for the legality of his successor to Vishnudevanand.
On February 22, 1999, the court in Allahabad, Uttar Pradesh issued an injunction prohibiting Vasudevananda from using the title Sankaracharya to raise funds until the dispute was resolved.
The dispute before the Supreme Court in Allahabad ended 2017 with the result that Vasudevanada has no claim and Swami Swaroopanada cannot have 2 chairs. It ordered a new election within 3 months. Until now no other candidate appeared, and so the chair is left, but Shankaracharya' Vasudevanand Saraswati did not stop working .
* Requisite qualifications for a Shankaracharya are contained in the following two verses of "Mathamnaya": "He who is unsullied, has subdued the senses, is well versed in the Vedas and Vedangas, and is conversant with the application of the shastras can obtain my Peeth otherwise, one devoid of these merits even if installed, is to be deposed by the wise and learned." (English translation by Court)