Short answers, pulled from the story.
The Ibadat Khana was constructed in the year 1575 by Mughal Emperor Akbar. This building stood within the newly built capital of Fatehpur Sikri, a city of red sandstone that rose from the arid plains of northern India.
Akbar invited scholars from Hinduism, Islam, Zoroastrianism, Christianity, and groups that modern observers might classify as atheists to the Ibadat Khana. Jain Acharyas Hir Vijay Suri and Jin Chandra Suri were regular attendees, and Christian priests from the Portuguese mission in Goa arrived to defend the cross.
The Ibadat Khana faded into obscurity and the physical structure vanished from the historical record for centuries. The site remained a subject of intense scholarly debate until excavations in the early 1980s by K. K. Muhammed confirmed its existence.
Akbar built the Ibadat Khana for the explicit purpose of hosting arguments that might dismantle his own understanding of the divine. He sought to understand the spiritual foundations of the diverse peoples under his rule and decided to create a physical space where the boundaries between faiths could be dissolved through debate.
The debates within the Ibadat Khana evolved from a search for common ground into the active construction of a new religious order known as the Din-i-Ilahi or the Faith of the Divine by the late 1580s. This syncretic amalgamation of pantheistic Islamic Sufism and the devotional Bhakti movements of Hinduism remained a secret society of the elite that died out shortly after Akbar's death in 1605.