The town was captured by the Portuguese Empire in the 16th century and was referred to as Ghallah.It was part of a series of fortified cities that the Portuguese had to control access to the Persian Gulf and the Gulf of Oman, like Khor Fakan, Muscat, Sohar, Seeb, Qurayyat and Muttrah. It was attacked and sacked by the Sultan of Muscat's forces in March 1811 as part of the ongoing Omani campaign against the maritime forces of Al-Qasimi. It was a Trucial State from 1936 to 1951, before being reincorporated into Sharjah. Kalba was still being referred to as Ghallah at the time of J. G. Lorimer's 1906 survey of the Persian Gulf and Oman, when it consisted of some 300 areesh houses, of Naqbiyin, Sharqiyin, Kunud and Abadilah tribes as well as a number of Baluchis and Persians. It was home to ten boats trading with ports in the Persian Gulf and India. Majid bin Sultan bin Saqr Al Qasimi was granted the Shamaliyah region, including Kalba, as a fiefdom by his brother, Sheikh Salim bin Sultan Al Qasimi, Ruler of Sharjah. Kalba was subsequently ruled jointly by his two sons Hamad bin Majid and Ahmad bin Majid. Hamad's son Said Bin Hamad Al Qasimi succeeded him in 1902, at the time when the ruler of neighbouring Fujairah, Hamad bin Abdallah Al Sharqi, managed to establish independence. Said bin Hamad lived in Ajman, leaving the administration of Kalba in the hands of a slave named Barut.
Trucial state
By the 1920s, he took up residency in Kalba again and in 1936 was recognised by the British as a Trucial Ruler as an incentive to grant landing rights to an emergency air-strip as a backup to the Imperial Airways runway and fort at Al-Mahatta in the city of Sharjah. In April 1937, the deposed Ruler of Sharjah, Khalid bin Ahmad Al Qasimi, married Aisha, the daughter of Sheikh Said bin Hamad Al Qasimi. Said bin Hamad died suddenly at the end of April 1937 while visiting Khor Fakkan. Said bin Hamad's son, Hamad, was still a minor and so Aisha moved quickly to establish a regency, travelling to Kalba and organising the town's defences. For many years Said bin Hamad had lived in Ajman and entrusted a slave by the name of Barut to manage Kalba on his behalf, and Aisha now arranged for Barut to once again take charge as Wali. She sent a message to Khalid bin Ahmad, who was in Ras Al Khaimah at the time. A period of intense political infighting and negotiation between the many involved parties now followed. In June 1937, the notable residents of Kalba selected the slave Barut as Regent for the 12-year-old Hamad, but this solution was not accepted by the British and Khalid bin Ahmad was selected as regent. Increasingly seen as an influential and unifying figure by the Bedouin and the townspeople of the East Coast, he ruled over Dhaid and Kalba until 1950, when he was too old and infirm to take a further role in affairs. He died that year and the rule of Kalba reverted to the direct administration of Sharjah. Although there are British records of an insurgency in 1952 this appears to have been settled. File:Quelba.jpg|alt=|thumb|Portuguese Fortress Kalba .Livro das plantas de todas as fortalezas, cidades e povoaçoens do Estado da India Oriental / António Bocarro . That notwithstanding, there were almost constant outbreaks of squabbling and disputes between Kalba and neighbouring Fujairah which broke out into open fighting over a land dispute after the UAE was founded in 1971 and, in 1972 the newly founded Union Defence Force was called in to take control of the fighting which, by the time the UDF moved in, had killed 22 and seriously injured a dozen more. The dispute was finally settled after mediation between Sheikh Rashid of Dubai and other Rulers and a statement announcing the settlement sent out on 17 July 1972.
City access
Khor Kalba is accessible by three roads. The first merges after Wadi Al Helou tunnel with Maliha Road which finally leads to the Sharjah-Kalba Road from Sharjah International Airport. There is also the Fujairah-Kalba Road. The Khor Kalba Road extends until the border with Oman, and is one of the exit–entry points between the UAE and Oman.
Rulers
Majid bin Sultan Al Qasimi
Hamad bin Majid Al Qasimi
Said ibn Hamad Al Qasimi
Hamad bin Said Al Qasimi
Saqr bin Sultan Al Qasimi
Britain recognized Kalba on 8 December 1936, and it was re-incorporated into Sharjah in 1952.
