Timeline of the Unification of Saudi Arabia

King Abdulaziz recaptured Riyadh, to become the first cornerstone in founding the Kingdom of Saudi Arabia. Following this, surrounding city residents, including al-Kharj, al-Hariq, al-Hawtah, Wadi ad-Dawasir, and al-Aflaj, pledged allegiance to King Abdulaziz.

King Abdulaziz annexed the cities of al-Mahmal, al-Shuaib, Shaqra, Tharmada, and al-Washm. Then, he expanded further until the entire Sudayr region became under his control.

King Abdulaziz annexed the city of Unayzah after defeating Ibn Rashid's army. Then, he annexed Buraydah and the rest of the Qassim Province to his rule.

King Abdulaziz's army reached al-Ahsa, where the Ottoman forces surrendered to the Saudi army and left the area by sea. All regions associated with al-Ahsa were then annexed.

The unification of Aseer is completed after the Battle of Hijla. The Saudi army entered Abha and took control up to the western borders of al-Mikhlaf al-Sulaymani to the west, reaching Najran.

King Abdulaziz dispatched an army to Hail until it surrendered and incorporated into the Saudi State.

King Abdulaziz sent an army led by his son, Prince Faisal (later King Faisal), to Abha, where he defeated Al Ayed once again and brought Aseer under Saudi rule.

The unification of Hejaz began, with the Saudi army reaching Taif and peacefully annexing Makkah al-Mukarramah.

Jeddah was besieged and unified, followed by the peaceful annexation of al-Madinah al-Munawwarah, mirroring the events in Makkah al-Mukarramah. Thus, the entire Hejaz was brought under the control of the Saudi State.

Al-Hassan al-Idrisi, the governor of Jazan, ceded control to King Abdulaziz. Previously under Saudi protection following a protection and defense treaty with King Abdulaziz, Jazan was fully integrated into the Saudi State and came under the complete administration of King Abdulaziz.

The unification of the Kingdom was officially announced, and a Royal Decree was issued to announce the unification and to name the country the Kingdom of Saudi Arabia, starting from Thursday, September 23, 1932.