Hakuin Ekaku, also known as Hakuin Zenji, lived from 1686 to 1769 in Japan. He was born in the small village of Hara in the province of Suruga. Hakuin was the second son of a samurai family, but he was not interested in following in his father's footsteps. Instead, he showed a great interest in Zen Buddhism from a young age.

At the age of fifteen, Hakuin left his family to become a monk at the nearby Shoin-ji temple. However, his initial experience with Zen practice was not fruitful, and he left the temple after three years. He then traveled to various temples and studied under different Zen masters, but he still could not find the answers he was looking for.

It was not until Hakuin met the Zen master Shoju Rojin that he had a breakthrough in his practice. Under Shoju's guidance, Hakuin experienced a profound spiritual awakening, and he dedicated himself to Zen practice. He spent the next few years in intense meditation and studying Buddhist scriptures.

In 1718, Hakuin returned to his hometown of Hara and began teaching Zen to the local villagers. He also traveled to other villages and towns, spreading the teachings of Zen Buddhism. Hakuin's teachings were simple yet profound, and he emphasized the importance of rigorous meditation and self-inquiry.

Hakuin's reputation as a skilled Zen master grew, and he attracted many students from all over Japan. He also wrote numerous texts on Zen, including "The Song of Zazen" and "The Embossed Tea Kettle." His teachings and writings had a significant impact on the development of Rinzai Zen in Japan.

Hakuin's most famous student was the renowned poet and Zen master Ryokan. He also had a significant influence on other prominent Zen masters, such as Takuan Soho and Bankei Yotaku.

Hakuin's legacy continues to this day, and he is considered one of the most influential figures in the history of Zen Buddhism. His teachings and writings are still studied and practiced by Zen students all over the world. Hakuin's dedication to rigorous meditation and his emphasis on the direct experience of enlightenment have made him a revered figure in the Zen tradition.