Here is history of 1st Sikh Guru, the founder of Sikhism and Japji sahib, Guru Nanak Dev Ji.

Guru Nanak Dev ji is the founder of the Sikh religion. He was born on 1469 at Talwandi (Nankana Sahib Pakistan). Mehta Kalyan Dass who was the father was an accountant in the employment of the local Muslim authorities.

Guru Nanak made friends with both Hindu and Muslim. At the age of six he was sent to the village school teacher for schooling in reading. He was then schooled in the study of Muslim literature and learned Persian and Arabic. At age 13 he refused to accept the sacred cotton thread from the Hindu priest. He said "Let mercy be the cotton, contentment the thread, continence the knot and truth the twist. O priest! If you have such a thread, Do give it to me. It'll not wear out, nor get soiled, nor burnt, nor lost. Says Nanak, blessed are those who go about wearing such a thread". Needless to say the Hindu priest was speechless.

As a young man, he would spend long hours absorbed in meditation and in religious discussions with Muslim and Hindu holy men. At age 16 he was married to Sulakhni, daughter of a pious merchant. He had two sons, Sri Chand and Lakshmi Chand three year later. Guru Nanak was persuaded by his parents to take a job as an accountant in charge of the stores of the Muslim governor of Daulat Khan Lodi. Guru Nanak would work during the days, but early in the mornings and late night he would meditate and sing hymns accompanied by his childhood friend Mardana. These sessions attracted a lot of attention and many people started joining the two.

Early one morning at the age of 30, Guru Nanak went to the river for his bath and did not come out and it was feared that he was drowned. After three days Guru Nanak appeared at the same spot from where he had disappeared. He was no longer the same person he had been and there was a divine light in his eyes and his face was resplendent. Guru Nanak was in the Holy Communion with God..
"There is but One God, His name is Truth, He is the Creator, He fears none, he is without hate, He never dies, He is beyond the cycle of births and death, He is self illuminated, He is realized by the kindness of the True Guru. He was True in the beginning, He was True when the ages commenced and has ever been True, He is also True now." (Japji) These words are enshrined at the beginning of the Sikh Holy Scriptures, the Guru Granth Sahib.

The next stage of his life began with extensive travels to spread the message of God. Once when Guru Nanak came to the small town of Saidpur in West Punjab he choose to stay there with Lalo. At the same time the local chief of the town Malik Bhago, who was quite wealthy and a very proudy man was holding a feast to which all holy men were invited. When Malik Bhago found out that Guru Nanak would not attend his feast, he was quite angry and had the Guru brought to him for questioning. When asked why he didn't join in the feast, the Guru sent for the meal served by Malik Bhago and also some of the simple meal served by Lalo. Holding these in separate hands he squeezed them, blood appeared out of the rich food of Malik Bhago, while milk oozed out of Lalos simple fare. Malik Bhago was put to shame and realized that his riches had been amassed by exploiting the poor, while what Lalo offered was the milk of hard earned honest work.

When Guru Nanak stopped at Hardwar a pilgrimage center on the Ganges river he found a large gathering of devotees. They were taking ritual baths in the holy river and offering water to the sun. When the Guru asked "Why do you throw water like that?" The pilgrims replied that they were offering it to their ancestors. Guru Nanak upon hearing this started throwing water in the opposite direction towards the west. When the pilgrims asked him what he was doing Guru Nanak replied "I am sending water to my farm which is dry". They asked, "How will water reach you crops so far away?" Guru Nanak replied, "If your water can reach your ancestors in the region of the sun, why can't mine reach my fields a short distance away?" The pilgrims realized their folly and fell at the Gurus feet.

Guru Nanak dressed in the blue garb of a Muslim pilgrim traveled to the west and visited Mecca, Medina and Baghdad. Arriving at Mecca, Guru Nanak fell asleep with his feet pointing towards the holy Kabba. When the watchman on his night rounds noticed this he kicked the Guru, saying, "How dare you turn your feet towards the house of God". At this Guru Nanak woke up and said, "Good man, I am weary after a long journey. Kindly turn my feet in the direction where God is not." When pilgrims and the holy men of the shrine gathered to hear Guru Nanak and question him, he sang in Persian;

"I beseech you, O Lord! pray grant me a hearing. You are the truthful, the great, the merciful, and the faultless Creator. I know for certain, this world must perish, And death must come, I know this and nothing else. Neither wife, nor son, nor father, nor brothers shall be able to help. I must go in the end, none can undo what is my fate. I have spend days and nights in vanity, contemplating evil. Never have I thought of good; this is what I am. I am ill-starred, miserly, careless, short-sighted, and rude. But says Nanak, I am yours, the dust of the feet of your servants."

While in Baghdad contradicting the Muslim priests views that their were only seven upper and as many lower regions Guru Nanak shouted out his own prayer saying,
"There are worlds and more worlds below them and there are a hundred thousand skies over them. No one has been able to find the limits and boundaries of God. If there be any account of God, than alone the mortal can write the same; but Gods account does not finish and the mortal himself dies while still writing. Nanak says that one should call Him great, and God Himself knows His ownself."
(Japji)

Guru Nanak and Mardana were both taken prisoner by the Mughal's. While in jail Guru Nanak sang a divine hymn about the senseless slaughter of the innocents by the Mughal invaders. Upon hearing it the jailer reported it to his king. Babar sent for the Guru and upon hearing him realized that Guru Nanak was a great religious figure. He asked for the Gurus forgiveness and set him free offering him a pouch of hashish. Guru Nanak refused saying the he was already intoxicated with the love and name of God.

After having spent a lifetime of traveling abroad and setting up missions, an aged Guru Nanak returned home to Punjab. He settled down at Kartharpur with his wife and sons. Pilgrims came from far and near to hear the hymns and preaching of the Master. Here his followers would gather in the mornings and afternoons for religious services.

Thus on 1539 in the early hours of the morning Guru Nanak merged with the eternal light of the Creator. When the followers lifted the sheet they found nothing except the flowers which were all fresh. The Hindus took theirs and cremated them, while the Muslims took their flowers and buried them.