The Declaration of the Unification of Saudi Arabia (Arabic: إعلان توحيد المملكة العربية السعودية, romanized: Īʿlān Taūḥīd Al-Mamlakah al-ʿArabīyah as-Suʿūdīyah) was officially announced by Prince Faisal bin Abdulaziz, the Viceroy of Hejaz and future monarch on behalf of King Abdulaziz ibn Saud on September 23, 1932 (corresponding to 21 Jumada al-Ula 1351 Hijri), at 9:00 am from al-Hamidiyah Palace in Mecca.

[4][5][6] The declaration marked the establishment of the fifth and final iteration of the Third Saudi State as well as the formal culmination of Abdulaziz's nearly thirty-years of political and military campaign to unite the Arabian Peninsula under a single unitary traditionalist Islamic polity.

[7]In 1934, nearly two years after the country's proclamation, Saudi Arabia and North Yemen went to war with each other over the territorial claims of al-Hudaydah, Jizan, Asir and Najran.

The war ended with swift Saudi victory where Jizan, Asir and Najran came under Riyadh's jurisdiction and a Treaty of Taif was signed between Ibn Saud and Yahya Hamid ed-Din that guaranteed 20 years of peace between the two neighboring states.

Although out of power in Riyadh, Rashidis were still bastioned in their ancestral homeland of Ha'il and elsewhere in northern Arabia in the territories of the pro-Ottoman Emirate of Jabal Shammar and frequently engaged with Ibn Saud's forces during the unification wars.

Ibn Saud's victory in 1902 paved the way for the emergence of a new puritanical irregular Wahhabi religious militia mostly composed of nomadic tribesmen, known as the Ikhwan (transl.

The Ikhwan formed a crucial part of Ibn Saud's bedouin army and supported much of his expansionist campaigns after the Battle of Riyadh.

The aim of the treaty was make Ibn Saud agree to not to attack the British protectorates of Kuwait, Qatar and the Trucial States.

[11][12][13] In the outbreak of World War I, Sharif of Mecca Hussein bin Ali declared the Great Arab Revolt against the Ottoman Empire, thereby seceding from the latter and establishing the Kingdom of Hejaz besides joining the side of the Allied forces.

In 1920, following the end of World War I, the Ikhwan engaged with the Kuwaiti forces in the battles of Hamdh and Jahra after Salim al-Sabah demonstrated intentions of building a commercial city in the south of Kuwait, which was now close to the territory of Emirate of Nejd and Hasa.

[15][16][17][18] Ibn Saud abandoned his desire to annex Kuwait after a British military intervention on the latter's side that resulted in a huge defeat to the Saudis.

Following the death of Abdulaziz al-Rashid in the battle over Qasim and the rampant waning of Ottoman influence in Arabia in the aftermath of World War I, the Rashidis began relying on British support to ward-off external threats to the emirate.

[28][29] However, some Ikhwan leaders defied the orders of Ibn Saud and proceeded to expand the Wahhabi realm into the British protectorates of Transjordan, Iraq and Kuwait.

In 1932, 17 prominent leading political, ministerial, consultative and administrative figures held multiple meetings at the house of Abdullah bin Muhammad al-Fadl, the chief aide to the Viceroy of Hejaz in al-Salama neighborhood of Taif to sign an official document of 'proposed system' before submitting it to Ibn Saud.

Issued at our palace in Riyadh on this day the seventeenth of the month of Jumada Ula, the year 1351As per the data released by the King Abdulaziz Foundation for Research and Archives (Darah), at almost 9:00 am Mecca Time on September 23, 1932, Prince Faisal announced from al-Hamidiyah Palace the renaming of the Kingdom of Hejaz and Nejd and its annexes to the Kingdom of Saudi Arabia[38] by reciting the Royal Decree No.

Following the declaration, a ceremony was held in the al-Hamidiyah Palace with Faisal and his aides before 101 rounds of artillery fires were shot to salute the historic day.