Guru Nanak who established Sikhism was its first Guru. After him there were nine more Gurus who were the highest religious authority. The last Guru, Guru Gobind Singh, proclaimed that after him the Guru of the Sikhs would be the holy book of Sikhism, Guru Granth Sahib.

The Great Gurus of Sikhism
 

Sequence	Takht Guru & Divine Attribute		Period
The First Guru:		Guru Nanak Dev Ji (Humility)	(1469 to 1539)
The Seond Guru:		Guru Angad Dev Ji (Obedience)	(1504 to 1552)
The Third Guru:		Guru Amar Das Ji (Equality)	(1479 to 1574)
The Fourth Guru:		Guru Ram Das Ji (Service)	(1534 to 1581)
The Fifth Guru:		Sahib Guru Arjan Dev Ji (Self Sacrifice)	(1563 to 1606)
The Sixth Guru:		Guru Hargobind Ji (Justice)	(1595 to 1644)
TheSeventh Guru:		Guru Har Rai Ji (Mercy)	(1630 to 1661)
The Eight Guru:		Guru Harkrishan Ji (Purity)	(1656 to 1664)
The Ninth Guru:		Guru Teghbahadur Ji (Tranquility)	(1621 to 1675)
The Tenth Guru:		Guru Gobind Singh Ji (Royal Courage)	(1666 to 1708)

Official website of the State Government of Maharashtra for the Gur-Ta-Gaddi event and development plan.