Nanak died in 1539, but before he did, he chose Guru Angad, who lived from 1504 to 1552, to be his successor. Angad used to go by the name Lahina, and he used to worship the Hindu goddess Durga. He was leading a group to the holy site of Javalamukhi, which is a temple in a town of the same name in the Indian state of Himachal Pradesh. As he passed through Kartarpur, the beauty of Nanak's hymns won him over right away. After that, the future Guru was completely loyal to his new master. His actions convinced Nanak that he would be a better successor than either of the Guru's two sons. Angad was a very obedient disciple. He didn't change anything about Nanak's teachings, and his time in charge was quiet.

When Angad died, the title of Guru went to Amar Das, who lived from 1479 to 1574. He was known for being completely loyal to the second Guru. Tradition says that Amar Das was a Vaishnava who spent his whole life trying to find a Guru. During a trip to the Ganges River, he heard Angad's daughter sing a hymn by Nanak. This made him decide to become a Sikh. When he became Guru, Amar Das was 73 years old. He took over the Panth as it was beginning to settle down after the excitement of its early years. Many Sikhs were born into the Panth, and the religion was no longer as enthusiastic and exciting as it was when Nanak led it. Amar Das thought that the Sikhs needed rituals to strengthen their faith, so he had a sacred well (baoli) dug and made it a pilgrimage site. He also made Baisakhi, Maghi, and Diwali into holidays and put together a book of sacred hymns called the Goindval Pothis. Also, because Sikhs had spread all over Punjab, he set up manjis, or dioceses, to help spread the faith and keep its followers better organizedd. Even though these things changed, the need to meditate on the nam didn't go away.

Guru Amar Das's son-in-law was Guru Ram Das, the fourth Guru, who lived from 1534 to 1581. He is probably best known for starting the town of Amritsar, which means "Pool of Nectar." It became the capital of the Sikh religion and is where the Harmandir Sahib (later called the Golden Temple), the most important place of worship in Sikhism, is located. He also got rid of the manjis and replaced them with masands (vicars). The masands were in charge of certain Sangat's (groups) and had to give the Guru reports and gifts from the Sikh community at least once a year. Guru Ram Das, who was very good at singing hymns, stressed the importance of this practise, which is still a big part of Sikh worship. Ram Das was from the Khatri caste and the Sodhi family. He chose his son Arjan to take over after him, and all of the Gurus who came after him were his direct descendants.

Guru Arjan's (who lived from 1563 to 1606) oldest brother, Prithi Chand, was very angry about his brother's appointment and tried to kill Arjan's only son, Hargobind, by poisoning him. Prithi Chand and his followers also spread hymns that they said the earlier Gurus had written. This made Arjan want to make a real copy of the hymns, which he did with the help of Bhai Gurdas and the Goindval Pothis. The Guru Granth Sahib is a version of the Adi Granth that has been added to. It is still the most important book of the Sikh faith, and Sikhs always treat it with the utmost respect and look to it for guidance, comfort, or peace.

During Arjan's lifetime, more and more people joined the Panth, especially farmers from the Jat caste. The Mughal governor of the Punjab was worried about the growth of the religion, and Emperor Jahangir was influenced by rumors that Arjan supported Jahangir's rebellious son Khusro. Guru Arjan was taken in by the Mughals, who then tortured him to death. But before he died, he told his son, the sixth Guru, Hargobind, that he should always carry weapons.

When Guru Hargobind (1595–1644) became the sixth Guru, the Panth changed from being only religious to being both religious and secular. Later, the order that Arjan gave to his son was called miri/piri, which means "temporal authority" or "spiritual authority." Hargobind was still the Guru, and as such, he kept doing what the five Gurus before him had done. In other words, he was a pir, which means he was a spiritual leader. He was also a mir, which means he was the leader of his people and had to protect them from tyranny with force. Hargobind's actions confirmed the new status of the Guru and the Panth, which can be seen in the architecture of Amritsar. The Harmandir Sahib, which represents piri, is across from the Akal Takht, which represents miri. So, when Hargobind stood between the Harmandir Sahib and the Akal Takht and buckled on two swords, it was clear that he had both spiritual and temporal power.

Hargobind fought with Mughal forces in the Punjab on and off. After four of these fights, he left Amritsar and took over Kiratpur at the base of the Shiwalik Hills. This was a much better spot because it was outside of the area that the Mughal government directly controlled. He lived there until he died in 1644.

Before he died, there was talk about who should take his place. Even though it was clear that his child or grandchild should take his place, it wasn't clear which of his children or grandchildren should do it. Hargobind had six children with his three wives. Gurditta, the oldest son, was his clear favorite for the job, but he had already died, and none of the other five seemed right for the job. Gurditta's older son, Dhir Mal, was turned down because he had made a deal with Emperor Shah Jahan from his seat in Jalandhar district. Har Rai, Gurditta's younger son, would become the seventh Guru because of this. But Dhir Mal kept making trouble for the traditional Panth and got a lot of Sikhs to follow him. He also said he had the holy book written by Guru Arjan and used it to back up his claim that he was the only real Guru.

Guru Har Rai's time in power, from 1630 to 1661, was mostly peaceful. He left Kiratpur and moved farther into the Shiwalik Hills, where he settled at Sirmur with a small group. From there, he would sometimes go out onto the plains of Punjab to visit the Sikhs and preach to them. In this way, he was helped by many masands who told him about the Sikhs and gave him money to help pay for the Panth's costs. The time of peace, however, did not last. Guru Har Rai had the same problems as Guru Arjan with the Mughals. Aurangzeb, who won the fight for the Mughal throne, beat his older brother Dara Shikoh and moved to Delhi. He then sent a message to Har Rai, telling him that, because Har Rai was thought to have helped Dara Shikoh, he had to give up his son Ram Rai as a hostage. Aurangzeb wanted the future Guru to learn how to live like a Mughal and become a supporter of the Mughal throne. Aurangzeb once asked Ram Rai to explain a line in the Adi Granth that seemed insulting and said that earthenware pots were made from the bodies of dead Muslims. This was a good example of how well this quest worked.

Ram Rai said that the words were written wrong. The original wording should have been "mitti beiman ki," which means "the dust that comes from the bodies of people who don't believe." When Har Rai heard this answer, he said he didn't want to see Ram Rai ever again. Ram Rai could never be the Guru because he changed Guru Nanak's words, which was a very bad thing to do. Instead, the position went to his younger brother, Hari Krishen, who got it when he was only five years old.

Aurangzeb called Guru Hari Krishen from the Shiwalik Hills to Delhi between 1656 and 1664. Hari Krishen got smallpox while he was in Delhi, which killed him. Before he died, he said, "Baba Bakale." This told his followers that his successor is the "old man" who lives in the village of Bakala and goes by the name "baba." Hari Krishen was trying to find Tegh Bahadur, who lived in Bakala and was Guru Hargobind's son from his second wife. He was also Guru Hari Krishen's grandfather's half brother.

As soon as people heard these words, they all ran to Bakala to claim the title. Makhan Shah was a trader who was caught in a violent storm at sea. In his fear, he promised to give the Sikh Guru 501 gold mohurs (coins) if he was saved. After the storm was over, the man who had survived went to the Punjab. He found out that the Guru lived in Bakala, so he went there. After Guru Hari Krishen died, he found out that more than one person claimed the title. He decided to put all of them to the test by giving each of them two gold mohurs. When he finally got to Tegh Bahadur, he had to give him the rest of what he had promised. Makhan Shah rushed up to the roof and yelled that he had found the real Guru.

Guru Gobind Singh (1666–1708), who was the most important Guru except for Guru Nanak, took over as leader of the Sikhs after Tegh Bahadur's death. Guru Tegh Bahadur's only child, Gobind Rai, whose name was changed to Gobind Singh around the time the Khalsa was formed, was born in Patna. His name was changed to Gobind Singh. At age five, he was taken to Anandpur, where he learned Sanskrit and Persian, as well as how to write poetry and fight. The fact that Aurangzeb killed his father in Delhi must have left a deep impression on the child. After he became Guru, he went to the Shiwalik Hills to keep learning for a few years. He became an adult as the leader of a small Shiwalik state. He fought in many wars against other Shiwalik chieftains and enjoyed hunting more than anything else.

Guru Granth Sahib, the holy book of Sikhs, is the Guru now and for all time to come.