Storia marittima persiana e iraniana: i navigatori dell'antico Oceano Indiano

Who Were the Persian Seafarers of the Ancient World?

Persian engagement with maritime trade predates the Sassanid Empire. The Achaemenid dynasty (550–330 BCE) controlled the Persian Gulf coast and commissioned Scylax of Caryanda to navigate from the Indus River to the Red Sea around 519 BCE — an expedition documented by Herodotus that suggests Persian interest in sea routes as instruments of imperial logistics. Under the Sassanids (224–651 CE), Persian Gulf merchants developed regular trading connections with India, Sri Lanka, and Southeast Asia, and Chinese sources from the Northern Wei period (386–534 CE) record Persian envoys arriving by sea. The port of Hormuz — whose name derives from the Sassanid-era settlement of Hormozd — was already a significant transit point before the Islamic conquests of the 7th century CE.

The transition from Sassanid to Islamic rule did not disrupt Persian maritime activity; it reorganised and, in many respects, expanded it. Persian sailors, merchants, and navigators continued to operate under the Umayyad and Abbasid caliphates, often retaining their language and technical knowledge while adopting Islam. The port of Siraf, excavated by David Whitehouse in the 1960s–70s, reached its peak between the 8th and 10th centuries CE — a period when its merchants maintained direct trading relationships with Tang and Song dynasty China, as documented in both the Akhbar al-Sin wa'l-Hind (c. 851 CE) and Chinese customs records from Guangzhou and Quanzhou.

What Was the Dhow and How Was It Built?

The Dhow — a broad category of lateen-rigged sailing vessels associated with the Persian Gulf and Arabian Sea — was distinguished for much of its history by its sewn-hull construction. Rather than iron nails, Persian Gulf boatbuilders fastened planks together using coir rope made from coconut fibre, a technique described by al-Masʿudi (c. 896–956 CE) in his Muruj al-Dhahab and by Ibn Battuta in his 14th-century Rihla. The method produced a hull with a degree of flexibility that may have helped vessels survive the stresses of open-ocean sailing; it also meant that repairs could be made at any port with access to coconut fibre, without requiring iron or specialist smithing tools.

The lateen sail — a triangular sail set on a long yard at an angle to the mast — allowed Dhows to sail closer to the wind than square-rigged vessels, making them well suited to the variable wind conditions of the Indian Ocean and the reversing monsoon system. Dhow types varied considerably by region and period: the boom, the baghla, and the sambuk each had distinct hull forms and rigging configurations suited to different routes and cargo types.

How Did Persian Sailors Navigate the Indian Ocean?

Persian Gulf navigators developed a sophisticated body of astronomical and hydrological knowledge for Indian Ocean passage-making. The kamal — a simple wooden board held at arm's length with a knotted string to measure the altitude of the Pole Star — is associated with Persian Gulf navigation and allowed pilots to maintain a consistent latitude on north–south passages. Ahmad ibn Majid (c. 1432–c. 1500 CE) compiled the Kitab al-Fawaʼid — a comprehensive navigational manual covering star positions, monsoon timing, coastal landmarks, and current patterns for routes from the Red Sea to China. Ibn Majid is traditionally (though controversially) credited with guiding Vasco da Gama from Malindi to Calicut in 1498.

The monsoon system — the seasonal reversal of winds across the Indian Ocean — was the structural foundation of Persian Gulf maritime trade. Outbound voyages from the Gulf to India and beyond were made on the southwest monsoon (roughly June–September); return voyages used the northeast monsoon (roughly November–March). The timing of departures from Siraf, Hormuz, and Basra was organised around monsoon windows in ways directly comparable to the tidal and seasonal scheduling documented at Chinese ports such as Quanzhou and Mingzhou.

Where Did Persian Sailors Trade, and What Did They Carry?

At its greatest extent, the Persian Gulf maritime trade network connected the Gulf ports to East Africa, western India, Sri Lanka, Southeast Asia, and China. Outbound cargoes from the Gulf included horses, dates, pearls, glassware, and textiles. Return cargoes included Indian cotton, spices, teak for boatbuilding, Chinese ceramics and silk, and East African ivory and gold. The Akhbar al-Sin wa'l-Hind (c. 851 CE) describes Chinese porcelain as a standard return cargo on Gulf-to-China voyages — a claim confirmed by the archaeological record at Siraf, where Tang and Song dynasty ceramics have been excavated in quantity.

The port of Hormuz, which replaced Siraf as the Gulf's dominant entrepôt after earthquakes damaged Siraf in the 10th century CE, became one of the most cosmopolitan trading cities of the medieval world. Ibn Battuta, visiting in the 14th century, described it as a place where merchants from Persia, Arabia, India, and China conducted business simultaneously. Marco Polo, passing through Hormuz around 1272 CE, described the local vessels as poorly built by European standards — a comment that likely reflects his unfamiliarity with sewn-hull construction rather than any actual deficiency in seaworthiness.

How Did Persian Maritime Culture Interact with Chinese Seafaring?

The intersection of Persian Gulf and Chinese maritime traditions is documented from at least the Tang dynasty (618–907 CE). Persian merchants maintained a community in Guangzhou large enough to have its own quarter and mosque by the 8th century CE; similar communities existed at Quanzhou and Yangzhou. Chinese sources refer to these merchants collectively as Bosi (波斯, "Persian"). The Jiu Tangshu (舊唐書, compiled 945 CE) records Persian envoys and merchants arriving by sea on multiple occasions during the 7th and 8th centuries.

The two maritime traditions operated on complementary seasonal schedules: Persian Gulf vessels arrived at Chinese ports on the northeast monsoon (winter) and departed on the southwest monsoon (summer). This complementarity — rather than direct competition — may help explain the relatively peaceful coexistence of Persian, Arab, Indian, and Chinese maritime interests in the pre-modern Indian Ocean, at least until the arrival of Portuguese naval power in the early 16th century CE disrupted the existing order.

Traditional Chinese Sailing Junk Model — The vessel type that Persian Gulf merchants encountered at Quanzhou and Guangzhou: built in the Zhoushan workshop tradition, with the batten sail and flat-bottomed hull that made the Chinese junk the dominant cargo carrier of the medieval East Asian seas.