Final answer:
The first compilation of the Guru Granth Saheb was installed in Harmandir Saheb in the year 1604, under the guidance of Guru Arjan, the fifth Sikh Guru.
Step-by-step explanation:
The first compilation of the Guru Granth Saheb was installed in Harmandir Saheb in the year 1604. Guru Arjan, the fifth Sikh Guru, compiled the Adi Granth, the initial version of the Sikh scripture, and installed it in the Harmandir Saheb, also known as the Golden Temple, located in Amritsar, India. This event is a significant milestone in Sikh history as the Guru Granth Sahib is considered the eternal living Guru in Sikhism.