For Sikhs, Diwali is particularly important because it celebrates the release from prison of the sixth guru, Guru Hargobind, and 52 other princes with him, in 1619.
The Sikh tradition holds that the Emperor Jahangir had imprisoned Guru Hargobind and 52 princes. The Emperor was asked to release Guru Hargobind which he agreed to do. However, Guru Hargobind asked that the princes be released also. The Emperor agreed, but said only those who could hold onto his cloak tail would be allowed to leave the prison. This was in order to limit the number of prisoners who could leave.
However, Guru Hargobind had a cloak made with 52 pieces of string and so each prince was able to hold onto one string and leave prison.
Sikhs celebrated the return of Guru Hargobind by lighting the Golden Temple and this tradition continues today.