Saqaliba (Arabic: صقالبة, romanized: ṣaqāliba, singular Arabic: صقلبي, romanized: ṣaqlabī) is a term used in medieval Arabic sources to refer to Slavs, and other peoples of Central, Southern, and Eastern Europe. The term originates from the Middle Greek slavos/sklavenos (Slav), which in Hispano-Arabic came to designate Slavic slaves.

The word was often used to refer specifically to Slavic slaves, but it could also refer more broadly to various other ethnicities of Eastern Europe traded by the Arab traders, as well as all European slaves in some Muslim regions like Spain and Portugal including those abducted from raids on Christian kingdoms of Spain and Portugal. According to Sudár and B. Szabó, the word Saqaliba meant 'forest dweller', regardless of ethnicity.

There were several major routes for the trading of Slavic slaves into the Arab world: through Central Asia for the East Slavs; through the Balkans for the South Slavs; through Central and Western Europe for the West Slavs and to al-Andalus. The Volga trade route and other European routes, according to Ibrahim ibn Jakub (10th century), were serviced by Radanite Jewish merchants. Theophanes mentions that the Umayyad caliph Mu'awiya I settled a whole army of 5,000 Slavic mercenaries in Syria who had defected from the Byzantine side in the 660s. After the battle of Sebastopolis in 692, Neboulos, the archon of the Slavic corps in the Byzantine army, and 30,000 of his men were settled by the Umayyads in the region of Syria.

In the Arab world, the Saqaliba served or were forced to serve in a multitude of ways: as servants, harem concubines, eunuchs, craftsmen, mercenaries, slave soldiers, and as Caliph's guards. In Iberia, Morocco, Damascus and Sicily, their military role may be compared with that of mamluks in the Ottoman Empire. In al-Andalus, Slavic eunuchs were so popular and widely distributed that they became synonymous with the term Saqāliba, though not all Saqaliba were eunuchs. Some Saqāliba became rulers of taifas (principalities) in Iberia after the collapse of the Caliphate of Cordoba in 1031. For example, Mujāhid al-ʿĀmirī organized the Saqaliba in Dénia to rebel, seize control of the city, and establish the Taifa of Dénia (1010–1227), which extended its reach as far as the island of Majorca.

The Arabic term ṣaqāliba derives from Greek Sklavoi and Sklavenoi (Σκλάβοι, Σκλαβηνοί), the Slavic ethnonym (used for the Sclaveni), entering Arabic usage in the 7th century. Due to the multitude of Slavic slaves, the term "slave" replaced Latin servus. The term was usually used for the Slavic peoples of central and eastern Europe. It was variously used for Slavic peoples and countries in the 10th century; Persian polymath Abu Zayd al-Balkhi (850–934) described three main centers of the Saqaliba: Kuyaba, Slawiya, and Artania, while traveller Ibrahim ibn Yaqub (fl. 961–62) placed the Saqāliba, Slavs, west of Bulgaria and east of other Slavs, in a mountainous land (Western Balkans), and described them as violent and aggressive.

The word was often used to refer specifically to Slavic slaves, but it was also broadly used for Eastern European slaves traded by the Arabs, as well as all European slaves in some Muslim regions like Spain and Portugal including those abducted from raids on Christian kingdoms of Spain and Portugal. According to Sudár and B. Szabó, the word Saqaliba also meant "forest dweller", regardless of ethnicity, in 10th-century Muslim usage.

The Volga trade route was established by the Varangians (Vikings) who settled in Northwestern Russia in the early 9th century. About 10 km (6 mi) south of the Volkhov River entry into Lake Ladoga, they established a settlement called Ladoga (Old Norse: Aldeigjuborg). It connected Northern Europe and Northwestern Russia with the Caspian Sea, via the Volga River. The Rus used this route to trade with Muslim countries on the southern shores of the Caspian Sea, sometimes penetrating as far as Baghdad. The route functioned concurrently with the Dnieper trade route, better known as the trade route from the Varangians to the Greeks, and lost its importance in the 11th century.

Saqaliba originally was used to denote Slavic people, however later it came to denote all European slaves in some Muslim regions like Spain including those abducted from raids on Christian kingdoms of Spain. The Franks started buying slaves from the Slavs and Avar Khaganate while Muslims also came across slaves in the form of mercenaries serving the Byzantine Empire and settlers in addition to among the Khazars. Most Slavic slaves were imported to the Muslim world through the border between Christian and Islamic kingdoms where castration centres were also located instead of the direct route. From there they were sent into Islamic Spain and other Muslim-ruled regions especially North Africa. The Saqaliba gained popularity in Umayyad Spain especially as warriors. After the collapse of the Umayyads, they also came to rule over many of the taifas. With the conversion of Eastern Europe, the trade declined and there isn't much textual information on Saqaliba after 11th century.