Naresuan is one of Thailand's most revered monarchs as he is known for his campaigns to free Ayutthaya from the vassalage of the Taungoo Empire.

[3] He required Maha Thammarachathirat to send his son—the Black Prince—to Bago as a royal hostage to ensure the king's fidelity.

[2]: 36, 67 The War of the first fall was ended by Bayinnaung, who installed Maha Thammaracha as a vassal king of Ayutthaya.

"Besides being gifted in military prowess, Naresuan who was highly intelligent, gained a great deal of general knowledge of the times.

"[5]: 43 Maha Thammaracha made Naret the Uparaja ("crown prince") of Phitsanulok as Naresuan at the age of 15.

[2]: 67–68, 75 [note 2] Naresuan joined his father and the King of Bago in an expedition to conquer Vientiane, the capital of the restored Lan Xang, but he contracted smallpox and had to return.

[2]: 77 In 1570, after seeing the fall of Ayutthaya to the Burmese, Baraminreachea, the Khmer King, took the opportunity to retake the lands lost to the Siamese.

At that time, King Naresuan was 24 years old and was aware that Phraya Chin Chantu was a Cambodian agent who took refuge in Ayutthaya under false pretenses to gather information on the Siamese court.

[note 3] According to Damrong, this raised Nanda's suspicions, who ordered his son, the Maha Uparaja Mingyi Swa, to remain in the capital and kill Naresuan.

Naresuan then "poured water on the earth from a gold goblet to proclaim to the devatas in the presence of the persons assembled, that from that day forth Siam had severed friendship with Hongsawadi and was no longer in amity as of yore.

"[2]: 85–86 According to Damrong, Naresuan then levied the Mons to join his campaign and marched onto Bago, intending to free the Siamese families held captive there.

There Surakamma was killed by "the royal gun used by Somdet Phra Naresuan while crossing the Satong river".

[2]: 87–88 Naresuan then held the "ceremony of swearing allegiance" with the people of Sukhothai, drinking water from the sacred pond of Puay Si.

In 1584 Naresuan brought down all of the men from the northern provinces to the Siamese capital of Ayutthaya in preparation for the attack of the Bago army.

[2]: 92–93 In the same year Nanda Bayin sent two separate armies, one under his uncle the viceroy of Pathein, and another from Chiang Mai under his younger brother Noratra Mangsosri.

[2]: 94–98  Then in 1586,[note 5] Naresuan defeated the Viceroy of Chiang Mai near Pa Mok and Bang Kaeo, capturing his encampment at Ban Saket with 10,000 soldiers, 120 elephants, 100 horses, 400 boats plus arms, ammunition, and provisions.

The Burmese army led by Phra Maha Uparat attacked Siam again, but Naresuan defeated it near Ban Khoi.

The Burmese army retreated back to Bago, losing many men, elephants, horses, arms, and ammunition.

Naresuan marched towards Suphan Buri and encamped his armies at Nong Sarai near the Thakhoi River.

Naresuan formed a battle plan which involved a retreat, allowing the Burmese to follow, and then attack the disordered advance with his main army.

[disputed – discuss] Naresuan built a pagoda on the site of the elephant battle as a victory monument.

[2]: 134 Naresuan brought before a council of judges those commanders he thought had disobeyed him or were negligent in their duties; they had been unable to follow him into the middle of the Burmese.

However, Somdet Phra Phanarat, a bhikkhu from Wat Yai Chai Mongkhon, calmed Naresuan enough to have the punishment rescinded.

[17] However, Jeremias van Vliet's account of Siam in early 1630s includes interviews with Siamese subjects who were contemporaries of King Naresuan and who insisted that the elephant combat, which resulted in the death of the Burmese crown prince at the hands of Naresuan (whom the Siamese called "the black prince"), did indeed happen.

[21] According to Terwiel, the "Burmese and European accounts stayed closer to what actually may have happened", and "Naresuan's much repeated challenge to hold a duel, even though it looms large in many Thai history books, should be relegated to a legendary tale.

He laid siege on the city for three months before retreating when the viceroys of Prome, Taungoo, and Ava sent relief forces.

[2]: 151–155 After these series of upheavals in the Burmese Empire, Naresuan decided to attack Bago again in 1599, using Arakan and Taungoo as allies.

He advanced as far as the Fang District of Chiang Mai Province before falling ill and then died after three days on 25 April 1605.

[2]: 173–180 Recent studies of Burmese records by historians of Silpakorn University showed that he returned to Wiang Haeng, where he died of disease, probably smallpox.