Chiranjivis are mortals who have been blessed or cursed with an
exceptionally long lifespan.They are born to accomplish extraordinary feats and
will live in this world till the purpose of their birth is fulfilled.There are
seven Chiranjivis mentioned in Hindu puranas and they are refered to as 'Saptha
Chiranjivi' meaning 'The Seven Chiranjivis'.
HANUMAN
Hanuman is the son of Lord Vayu,the wind god.During his childhood,he
once mistook the sun for a sweet fruit and reached for it.Indra,the Lord of
Devas was terrified of the consequences and struck him with his
Vajrayutham.This made Hanuman unconscious and he fell down.On seeing this,Lord
Vayu got very angry and he withdrew from all the creations .To please
Vayu and bring back life to the Earth,all the Gods gave Hanuman multiple boons
making him a Chiranjivi!
VIBISHANA
Vibishana is the righteous brother of Ravana,the demon king of
Lanka.When Ravana abducted Sita,wife of Lord Rama,an avatar of Vishnu,Vibishana
renounced his brother and joined Lord Rama in his battle against Ravana.Lord
Rama praised Vibishana for his dharmic ways and blessed him to remain on Earth
and protect Dharma by making him a Chiranjivi .
MAHABALI
Mahabali is a virtuous and powerful asura king who was tricked into
giving away his kingdom by Lord Vishnu as the devas were fearful of his
might.However,Lord Vishnu was deeply touched by the devotion and righteousness
of King Mahabali that he granted him a boon.The king asked Vishnu to allow him
to visit his people once in a year.This day is celebrated by his people as
'Onam ' in Kerala.Lord Vishnu also blessed him to live as a Chiranjivi.
MARKENDAYA
Markendaya is a great sage and staunch devotee of Lord Shiva. His
parents, Sage Mrikandu and Marudvati were childless for a long time and prayed
to Lord Shiva for a child.Lord Shiva fulfilled their wish and asked them to
choose between an exceptional son who would live for sixteen years or an
ordinary son who would live much longer.They chose the former and
thus,Markendaya was destined to die on his sixteenth birthday.
On his sixteenth birthday,Markendaya saw his parents in deep
sorrow and asked them for the reason behind their unhappiness.After much
persuasion,they told him about the boon Lord Shiva had given them.Markendaya
left the house and began worshipping a Shiva Linga.Lord Yama sent his
messengers to take away Markendaya's life but they could not suceed as
Markendaya was holding the Shiva Linga tightly.Seeing this,Lord Yama came and
threw a rope around Markendaya which accidentally hit the Shiva Linga.Lord
Shiva,who was deeply moved by Markendaya's devotion kicked Yama and blessed him
that he will always remain sixteen,making him a Chiranjivi .
SAGE VYASA
Sage Vyasa is the son of Sage Parashara and Satyavathi .He is the
foremost of Sages and is the compiler of the Holy Vedas. The great Indian Epic
"Mahabaratha" was composed by Vyasa to enable us to understand the
values which we have adhere to in life and is considered as the 'Fifth Veda'.He
also composed the eighteen puranas,Brahmasutras and Bhagavatham,the
story of Lord Krishna.Sage Vyasa is considered to be an avatar of Lord Vishnu
and is living as a Chiranjivi.
SAGE PARASURAMA
Sage Parasurama is the son of Sage Jamadagni and Renuka.He is an avatar
of Lord Vishnu,born to rid the world of unrighteous Kshatriyas.Parasurama also
plays a very important role in the Mahabaratha as the Guru of Bhishma and
Karna.He is a Chiranjivi and will be the martial arts Guru of Vishnu's final
avatar,Kalki.
ASHWATHAMA
Aswathama is the son of son of Guru Dronacharya and Kripi.He fought
alongside the Kauravas in the Kurukshetra war.Lord Krishna cursed Ashwathama to
remain a Chiranjivi and suffer miserably for unleashing the Brahmastra on
Uthara's womb to kill the unborn son of Abhimanyu.It is believed that he will
be redeemed from this curse in the next yuga.
http://www.hindufaqs.com/seven-immortals-chiranjivi-hindu-mythology-part-2/
https://www.quora.com/Who-are-the-seven-chiranjeevis-in-Hindu-mythology
http://www.hindudevotionalblog.com/2012/03/seven-chiranjeevis-in-hinduism.html
https://en.wikipedia.org/wiki/Vibhishana
http://www.bhagavatam-katha.com/sage-story-sage-markandeya-winning-over-death/
https://en.wikipedia.org/wiki/Bhishma