Soon after taking oath, Koshyari, who had served as a college teacher in Uttar Pradesh's Etah, also greeted all teachers on the occasion of Teachers Day, (September 5).
Earlier, Chief Justice Pradeep Nandrajog of the Bombay High Court administered the oath of office and secrecy to the new Governor at the sprawling Raj Bhavan facing the Arabian Sea.
Surprising all the dignitaries and invitees, Koshyari read out the entire oath in Marathi and the gathering expressed its approval with a thunderous round of clapping.
Chief Secretary Ajoy Mehta read out the warrant of appointment issued by the President Ram Nath Kovind and the event began and concluded with the playing of National Anthem by the Police Band.
Besides Chief Minister Devendra Fadnavis, Union Ministers Arvind Sawant and Ramdas Athawale, state ministers Chandrakant Patil, Vinod Tawde, Eknath Shinde, Subhash Desai, Diwakar Raote, and Suresh Khade, dignitaries and ministers from Uttarakand like H. S. Rawat, Subodh Uniyal, Rekha Arya, Dhan Singh Rawat, Almora MP Ajay Tamta, other MPs and legislators were also present.
Maharashtra Lokayukta, Justice M. L. Tahiliyani, Right to Services Commissioner Swadhin Kshatriya, State Chief Election Commissioner U.P.S. Madan, Director General of Police Subodh Jaiswal, Mumbai Commissioner of Police Sanjay Barve, Principal Secretary, Protocol, Nandkumar, Mumbai University Vice Chancellor Suhas Pednekar, SNDT Women's University Vice Chancellor, Dr Shashikala Wanjari were other prominent personalities present.
Koshyari, 77 takes over from C.V. Rao, whose term ended earlier this week.
Prior to the swearing-in ceremony, Koshyari visited and prayed the famed Siddhivinayak Temple in Prabhadevi dedicated to Lord Ganesha, even as the 10-day Ganeshotsav is being celebrated with religious fervor all over the state since September 2.
A veteran politic with over five decades in public life, he plunged into active politics from his student days, later worked as a college teacher in UP, founded and edited a weekly publication 'Parvat Piyush' since 1975, and later authored two books on the Uttarakhand state.
Subsequently, he joined the Rashtriya Swayamsevak Sangh (RSS), was jailed during the Emergency, served as Member of Rajya Sabha and as legislator, state minister, then Chief Minister, later as Leader of Opposition and also as Uttarakhand President of Bharatiya Janata Party.
Popular as the 'Peoples Leader' with massive grassroots following in Uttarakhand, Koshyari has founded several schools and learning institutions in his home state.
( With inputs from IANS )