In the 11th century BC, land routes through Arabia were greatly improved by using the camel as a beast of burden, and frankincense was carried from its production centre at Qana (now known as Bir 'Ali) to Gaza in Egypt. The camel caravans also carried gold and other precious goods which arrived in Qana by sea from India.

The chief incense traders were the Minaeans, who established their capital at Karna (now known as Sadah), before they were superseded by the Sabaeans in 950 BC. The Sabaean capital was Ma'rib, where a large temple was built. The mighty Sabaean civilisation endured for about 14 centuries and was based not only on the spice trade, but also on agriculture. The impressive dam, built at Ma'rib in the 8th century, provided irrigation for farmland and stood for over a millennium. Some Sabaean carved inscriptions from this period are still extant.

The Himyarites established their capital at Dhafar (now just a small village in the Ibb region) and gradually absorbed the Sabaean kingdom. They were culturally inferior to the Sabaeans and traded from the port of al-Muza on the Red Sea. By the first century BC, the area had been conquered by the Romans.

With the rise of the great ancient civilizations in Egypt, Mesopotamia, and along the Mediterranean Sea, historic Yemen became an important overland trade link between these civilizations and the highly prized luxury goods of South Arabia and points east and south. As a result, several pre-Islamic trading kingdoms grew up astride an incense trading route that ran northwest between the foothills and the edge of the desert. First, there was the Minaean kingdom, which lasted from about 1200 to 650 BC, and whose prosperity was due mainly to the trade of frankincense and spices. The large and prosperous kingdom of Saba' (Sheba), founded in the 10th century BC and ruled by Bilqis, the queen of Sheba, among others, was known for its efficient farming and extensive irrigation system built around a large dam constructed at Ma'rib.

Farther south and east, in the region that would later become South Yemen, were the Qataban and Hadhramaut kingdoms, which also participated in the incense trade. The last of the great pre-Islamic kingdoms was that of Himyar, which lasted from about the 1st century BC until the 500s AD (seeHimyarites). At their heights, the Sabaean and Himyarite kingdoms encompassed most of historic Yemen.

Because of their prominence and prosperity, the states and societies of ancient Yemen were collectively called Arabia Felix in Latin, meaning "Happy Arabia." However, when the Romans occupied Egypt in the 1st century BC they made the Red Sea their primary avenue of commerce. With the decline of thecaravan routes, the kingdoms of southern Arabia lost much of their wealth and fell into obscurity. Red Sea traffic sailed past Yemen, and what seaborne commerce Yemen engaged in had little impact on the country's interior.

The Tihamah region, which was hot, humid, swept by sandstorms, and clouded in haze, isolated the comparatively well-watered and populous highlands. The weakened Yemeni regimes that followed the trading kingdoms were unable to prevent the occupation of Yemen by the Christian Abyssinian kingdom (modern Ethiopia) in the 4th and early 6th centuries AD and by the Sassanids of Persia in the later 6th century, just before the rise of Islam.