Buddhists also celebrate Diwali in their quiet way. They chant the mantras and remember Emperor Ashoka who converted to Buddhism on this day. Hence the Buddhists also know the festival as Ashok Vijayadashami. Their temples and monasteries are well decorated during this time and the Buddha is worshiped with full honors.
Significance in Sikhism -
The story of Diwali for the Sikhs is a story of the Sikh struggle for freedom. From the time of Guru Nanak (1469 1539), the founder of Sikhism.When the Muslim king was ruling he locked up the Guru but while the king had tried to make him eat he refused and fasted. It was then realized that outside the palace people had gathered around with lanterns, candles, torches and protested to set the Guru free and the king had eventually agreed that his greediness had got in the way of his responsibilities and released the Guru and the people celebrated his release known as Diwali.
Bandi Chhorh Divas
For Sikhs, Diwali is particularly important because it celebrates the release from prison of the sixth guru, Guru Hargobind Ji, (hence also called "Bandi Chhorh Diwas" or "the day of release of detainees") and 52 other princes with him, from the Gwalior Fort in 1619.
The Mughal Emperor Jahangir had imprisoned Guru Har Gobind Ji and 52 other rajas (princes). Emperor Jahangir had imprisoned the sixth Guru because he was afraid of the Guru's growing, following and power. 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 made a large cloak with 52 tassels and so each prince was able to hold onto one tassel and leave prison.
Sikhs celebrated the return of Guru Hargobind Ji by lighting the Golden Temple and this tradition continues today.
Martyrdom of Bhai Mani Singh Ji
Another important Sikh event associated with Diwali is the martyrdom in 1737 of the elderly Sikh scholar and strategist Bhai Mani Singh, the Granthi (keeper/reader of Sikh scripture) of Harmandir Sahib (Golden Temple). He had refused to or was unable to pay jizya - a special tax imposed by the Mughal Empire on non-Muslims - on a religious meeting of the Khalsa on the Diwali day. This and other Sikh martyrdoms gave further momentum to the Khalsa struggle for freedom and eventual success in establishing the Khalsa rule north of Delhi
Bhai Mani Singh was a great scholar and he transcribed the final version of Guru Granth Sahib which was dictated to him by Guru Gobind Singh Ji in 1704. He took charge of Harmandir Sahib's management in 1708. In 1737, he received permission from the Mughal governor of Punjab, Zakariya Khan, to hold a religious meeting on Diwali for a massive tax of Rs. 5,000 (some authors say it was Rs 10,000). Invitations were sent to the Sikhs all over India to join Bandi Chhorh Diwas celebrations at Harmandir Sahib. Bhai Mani Singh thought he would collect the tax-money from the Sikhs who would assemble for the purpose of Diwali Celebrations as subscriptions. But Bhai Mani Singh Ji later discovered that Zakariya Khan secretly planned to kill the Sikhs during the gathering. Bhai Mani Singh Ji immediately sent messages to all the Sikhs not to turn up for celebrations. As Bhai Mani Singh could not arrange for the tax to be paid, Zakariya Khan ordered Bhai Mani Singh's execution at Lahore by ruthlessly cutting him to death, limb-by-limb. Ever since, the great sacrifice and devotion of martyr Bhai Mani Singh Ji is remembered on the Bandi Chhorh Diwas (Diwali) celebration.
Uprising against the Mughal Empire
The festival of Diwali became the second most important day after the Baisakhi, when Khalsa was formally established by the Tenth Guru Gobind Singh in 1699.
The Sikh struggle against Mughal Empire's atrocities on non-Muslims, especially on Sikhs, which intensified in the 18th century, came to be centered around this day. After the execution of Banda Bahadur in 1716, who had led the agrarian uprising in Punjab, the Sikhs started the tradition of deciding matters concerning the community at the biennial meetings which took place at Amritsar on the first of Baisakh and at Diwali. These assemblies were known as the Sarbat Khalsa and a resolution passed by it became a gurmata (decree of the Guru).
Happy Diwali