The history of Saudi Arabia as a nation state began with the emergence of the Al Saud dynasty in central Arabia in 1727 and the subsequent establishment of the Emirate of Diriyah. Pre-Islamic Arabia, the territory that constitutes modern Saudi Arabia, was the site of several ancient cultures and civilizations; the prehistory of Saudi Arabia shows some of the earliest traces of human activity in the world.
The Hejaz is a region that includes the majority of the west coast of Saudi Arabia, covering the cities of Mecca, Medina, Jeddah, Tabuk, Yanbu, Taif and Baljurashi. It is thus known as the "Western Province", and it is bordered in the west by the Red Sea, in the north by Jordan, in the east by the Najd, and in the south by the Region of 'Asir. Its largest city is Jeddah, which is the second-largest city in Saudi Arabia, with Mecca and Medina, respectively, being the fourth- and fifth-largest cities in the country.
Abdulaziz bin Abdul Rahman Al Saud, known in the West as Ibn Saud, was an Arab political and religious leader who founded Saudi Arabia – the third Saudi state – and reigned as its first king from 23 September 1932 until his death in 1953. He had ruled parts of the kingdom since 1902, having previously been Emir, Sultan, and King of Nejd, and King of Hejaz.
The Hashemites, also House of Hashim, are the royal family of Jordan, which they have ruled since 1921, and were the royal family of the kingdoms of Hejaz (1916–1925), Syria (1920), and Iraq (1921–1958). The family had ruled the city of Mecca continuously from the 10th century, frequently as vassals of outside powers, and ruled the thrones of the Hejaz, Syria, Iraq, and Jordan following their World War I alliance with the British Empire.
Taif is a city and governorate in the Mecca Province of Saudi Arabia. Located at an elevation of 1,879 m (6,165 ft) in the slopes of the Hijaz Mountains, which themselves are part of the Sarat Mountains, the city has a population of 563,282 people in 2022, making it one of the most populous city in the kingdom.
Jeddah, alternatively transliterated as Jedda, Jiddah or Jidda, is a port city in Makkah Province, Saudi Arabia, located along the Red Sea coast in the Hejaz region. Jeddah is the commercial center of the country. It is not known when Jeddah was founded, but Jeddah's prominence grew in 647 when the Caliph Uthman made it a travel hub serving Muslim travelers going to the holy city of Mecca for Islamic pilgrimage. Since those times, Jeddah has served as the gateway for millions of pilgrims who have arrived in Saudi Arabia, traditionally by sea and recently by air.
The Emirate of Diriyah, also known as the First Saudi State, was established in February 1727. In 1744, the emir of a Najdi town called Diriyah, Muhammad bin Saud, and the religious leader Muhammad ibn Abd al-Wahhab formed an alliance to found a socio-religious reform movement to unify the many states of the Arabian Peninsula.
Ali bin Hussein, was King of Hejaz and Grand Sharif of Mecca from October 1924 until he was deposed by Ibn Saud in December 1925. He was the eldest son of King Hussein bin Ali and a scion of the Hashemite family. With the passing of the kingship from his father he also became the heir to the title of caliph, but he did not adopt the office and the style of caliph.
The Hashemite Kingdom of Hejaz was a state in the Hejaz region of Western Asia that included the western portion of the Arabian Peninsula that was ruled by the Hashemite dynasty. It was self-proclaimed as a kingdom in June 1916 during the First World War, to be independent from the Ottoman Empire, on the basis of an alliance with the British Empire to drive the Ottoman Army from the Arabian Peninsula during the Arab Revolt.
The Battle of Jeddah or the siege of Jeddah took place in 1925, as part of the Ibn Saud's campaign to conquer the Kingdom of Hejaz. Jeddah was the last major stand of the Hashemites against the Saudis.
The Unification of Saudi Arabia was a military and political campaign in which the various tribes, sheikhdoms, city-states, emirates, and kingdoms of most of the central Arabian Peninsula were conquered by the House of Saud, or Al Saud. Unification started in 1902 and continued until 1932, when the Kingdom of Saudi Arabia was proclaimed under the leadership of Abdulaziz, known in the West as Ibn Saud, creating what is sometimes referred to as the Third Saudi State, to differentiate it from the Emirate of Diriyah, the First Saudi State and the Emirate of Nejd, the Second Saudi State, also House of Saud states.
Sultan bin Bajad bin Humaid al-'Utaybi was the Sheikh of the Otaibah tribe and one of the prominent leaders of the Ikhwan movement in the Arabian Peninsula. This tribal army supported King Abdulaziz in his efforts to unify Saudi Arabia between 1910 and 1927.
The Sharifate of Mecca or Emirate of Mecca was a state, non-sovereign for much of its existence, ruled by the Sharif of Mecca. A sharif is a descendant of Hasan ibn Ali, Muhammad's grandson. In Western sources, the prince of Mecca was known as Grand Sherif, but Arabs have always used the appellation "Emir".
The Saudi conquest of Hejaz or the Second Saudi-Hashemite War, also known as the Hejaz-Nejd War, was a campaign engaged by Saudi Sultan Abdulaziz to take over the Hashemite Kingdom of Hejaz in 1924–25, ending with conquest and incorporation of Hejaz into the Saudi domain.
The Taif massacre was an incident that followed the short 1924 Battle of Taif; the entire episode is also known as the al-Taif incident. The battle and resultant massacre comprised the first major standoff of the Second Hashemite-Saudi War. Following a short siege, the city was abandoned by Hashemite forces and then capitulated to the battle-ready Ikhwan force under the command of Abdulaziz Ibn Saud. The Ikhwan troops took out their rage on the residents of the city. In the resulting bloodbath, some 300-400 Ta'if residents were massacred.
The First Saudi–Hashemite War, also known as the First Nejd–Hejaz War or the al-Khurma dispute, took place in 1918–19 between Abdulaziz Ibn Saud of the Emirate of Nejd and Hasa and the Hashemites of the Kingdom of Hejaz.
Saudi National Day is a public holiday in Saudi Arabia celebrated annually on 23 September to commemorate the proclamation that renamed the Kingdom of Nejd and Hejaz as the Kingdom of Saudi Arabia in 1932 through a royal decree by King Abdulaziz ibn Saud. It was founded in 1965 on its 33rd anniversary by King Faisal bin Abdulaziz in order to replace the Royal Seating Day and was made a public holiday by King Abdullah bin Abdulaziz in 2005. Saudi National Day is one of the three non-religious holidays observed in the country, other being the Saudi Founding Day and Saudi Flag Day.
The Hejaz Air Force or Hejaz Flying Corps was the aerial component of the armed forces of the short-lived Kingdom of Hejaz and its successor the Kingdom of Hejaz and Nejd. Claiming to be the oldest Air Force on the Arabian Peninsula, the service was a very small entity, numbering at most nine aircraft at any time. It operated intermittently between 1921 and 1932, battling with staff shortages and aircraft availability; often only two aircraft were operational at any time. The personnel came from many nations, with pilots coming from Germany, Greece, Italy, Russia and the United Kingdom, as well as from the kingdom itself after the flight of the first Arab pilot, Abdul Salam Sarhan, in 1923. It provided aerial reconnaissance and bombardment to support the army against the much larger land forces of Ibn Saud during the Hejaz-Nejd War, including bombing attacks on Jeddah and Mecca. Its successor is the Royal Saudi Air Force.
The Battle of Turubah was fought on May 26, 1924, between the forces of Hussein bin Ali, under the command of his son Abdullah bin Al-Hussein, and forces under the command of Abdulaziz bin Abdul Rahman Al Saud. It was a larger part of the Hejaz-Nejd War, as well as the Al-Khurma dispute. The battle resulted in the end of Hussein's hopes to expand into the Arabian peninsula, as well as opening the way for Ibn Saud to fortify his own control over the region, which in turn would eventually lead to the creation of Saudi Arabia.
The Declaration of theUnification of Saudi Arabia was officially announced by Prince Faisal bin Abdulaziz, the Viceroy of Hejaz on behalf of King Abdulaziz ibn Saud on September 23, 1932, at 9:00 am from al-Hamidiyah Palace in Mecca. Faisal read out the Royal Decree No. 2716 issued by Abdulaziz ibn Saud on September 18, 1932, that renamed the Kingdom of Hejaz and Nejd and its annexes as the Kingdom of Saudi Arabia.
Sultanate of Najd 
Kingdom of Hejaz 
Sultan bin Bajad 