Muscat is the capital and most populous city in Oman. It is the seat of the Governorate of Muscat. According to the National Centre for Statistics and Information (NCSI), the population of the Muscat Governorate in 2022 was 1.72 million. The metropolitan area includes six provinces, called wilayat, and spans approximately 6,500 km2 (2,500 sq mi). Known since the early 1st century CE as a leading port for trade between the west and the east, Muscat was ruled successively by various indigenous tribes, as well as by foreign powers such as the Persians, the Portuguese Empire and the Ottoman Empire. In the 18th century, Muscat was a regional military power: its influence extended as far as East Africa and Zanzibar. As an important port town in the Gulf of Oman, Muscat attracted foreign traders and settlers such as the Persians, the Balochs and the Sindhis. Beginning in 1970, after the accession of Qaboos bin Said as the Sultan of Oman, Muscat experienced rapid infrastructural development; it developed a vibrant economy and became a multi-ethnic society. The Globalization and World Cities Research Network classifies Muscat as a Beta-level Global City.