There is also a religious movement called Valmikism that is solely based on Valmiki’s teachings and principles.

His early life:
Maharishi Valmiki was born as Ratnakara to sage Prachetasa. At a very young age he went to the forest and got lost. A hunter that was passing by saw him and took him under his own care, over the years he forgot his original parents under the parenthood of his newly found parents. Later when he grew up, he was married to a girl from a hunter’s family.
Turning into a robber:
Being bought up in a poor hunter’s family, he didn’t have any measures to feed his family, so he started to hunt in the forests. He robbed the people passing through the forests.
Meeting Narada:
One day when saint Narada was passing by the forest, he was attacked by Ratnakar. While Narada was playing his Veena and praising Lord Rama, he saw a transformation in Ratnakar. He then asked Ratnakar, if the family for which he was robbing others ,will share his sins also. Ratnakar went to his home and asked the same question to his family, to which he received a negative answer.
He immediately went back to Narada, Who taught him to meditate with chanting the name of Lord Rama, till he came back.
Ratnakar got so immersed in the mediation over years that when Narada returned, he saw that Ratnakar was totally covered by ant-hills. He immediately removed all the ant-hills from his body and told Ratnakar that his Tapasya has paid of and that the Lord was pleased with him. Ratnakara was bestowed with the honor of a Brahmarshi and given the name of Valmiki, since he was reborn from the Valmika (the ant-hill). Sage Valmiki founded his ashram at the banks of River Ganga.

Writing Ramayana:
One day when in the ashram of Valmiki, Narada narrated him the story of Lord Rama. After that Valmiki received a vision from Brahma in which the lord instructed him to write Ramayana in form of slokas, Which he obediently followed.