Neem Karoli Baba, also known as Maharaj-ji, was a Hindu guru and devotee of the Hindu deity Hanuman. He was born as Lakshman Narayan Sharma around 1900 in Akbarpur village in Firozabad district, Uttar Pradesh, India, into a wealthy Brahmin family. At the age of 11, he left home to become a wandering sadhu, but later returned home and lived a settled married life, fathering two sons and a daughter.

In 1958, Neem Karoli Baba, then known as Baba Lakshman Das, embarked on a train journey without a ticket. The conductor forced him off the train at the village of Neem Karoli in Farrukhabad district, Uttar Pradesh. After the train failed to start, Baba made a deal with the railway officials. He agreed to board the train again on the condition that a railway station would be built in Neem Karoli and that sadhus (holy men) would be treated better by the railway company. The officials agreed, and after blessing the train, it started moving again. As a result, a train station was built at Neem Karoli, and Baba settled in the village, where he was named after it.

Neem Karoli Baba wandered extensively throughout Northern India, adopting various names such as Lakshman Das, Handi Wallah Baba, Tikonia Walla Baba, Tallaiya Baba, and Chamatkari Baba, depending on the places he visited. He spent time in Vrindavan and Kainchi, where he established ashrams. The Kainchi Dham ashram, built in 1964 with a Hanuman temple, became an important pilgrimage site.

On September 11, 1973, Neem Karoli Baba passed away in a hospital in Vrindavan. He had been traveling by train from Agra to Kainchi but stopped at Mathura railway station due to chest pains. He was taken to the hospital in Vrindavan, where he slipped into a diabetic coma and eventually passed away. His samadhi shrine was constructed within the Vrindavan ashram complex, which also houses some of his personal belongings.

Neem Karoli Baba gained recognition outside India for his influence on a number of Americans who traveled to India in the 1960s and 70s. Notable individuals influenced by him include spiritual teachers Ram Dass and Bhagavan Das, as well as musicians Krishna Das and Jai Uttal. His teachings continue to inspire and guide many people to this day.

Neem Karoli Baba was a lifelong practitioner of bhakti yoga, emphasizing devotion to God through selfless service (seva). He was known by different names and appeared in various parts of India. He did not give discourses but conveyed teachings through simple stories and gestures. Baba emphasized surrendering to God's will and letting go of attachment and ego. Notable disciples include Ram Dass, Bhagavan Das, Jai Uttal, Krishna Das, and Lama Surya Das.

Neem Karoli Baba had a profound influence on individuals such as Steve Jobs, Julia Roberts, and Mark Zuckerberg. His teachings inspired the founding of the Seva Foundation, focused on preventing and treating blindness, and the Love Serve Remember Foundation, dedicated to preserving his teachings. The documentary "Windfall of Grace" explores the experiences and devotion of both Indian and American devotees of Neem Karoli Baba.