Indochina is a peninsula in Southeast Asia that sits between India and China, which is exactly how it got its name. The term covers the mainland portion of Southeast Asia, including Vietnam, Cambodia, Laos, Thailand, Myanmar, and the western portion of Malaysia. It spans from roughly 5 to 30 degrees north latitude and 90 to 110 degrees east longitude. Depending on context, “Indochina” can refer to this entire peninsula or, more narrowly, to the three countries that made up the former French colony: Vietnam, Cambodia, and Laos.
Where the Name Comes From
European observers coined the term in the early nineteenth century after noticing that the region’s cultures seemed to blend Indian and Chinese elements. Across much of the peninsula, people practiced Theravada Buddhism and used writing systems derived from Indian scripts. Along the eastern coast, particularly in Vietnam, people lived under a Confucian political system and used a writing tradition rooted in Chinese characters. To outsiders unfamiliar with the region’s deep internal diversity, this made the peninsula look like a cultural bridge between two giant civilizations, so they called it “Indo-China.”
The name was always a simplification. The peninsula is home to dozens of distinct ethnic groups, languages, and traditions that don’t fit neatly into either an “Indian” or “Chinese” category. Only one major language family in the region, the Annamese-Muong group (which includes Vietnamese), is considered an exclusively native product of the peninsula. The rest belong to Mon-Khmer, Thai, Tibeto-Burman, Malayo-Polynesian, and other language families that stretch well beyond the region’s borders.
The Broader Peninsula
In its widest geographical sense, the Indochinese Peninsula includes six countries: Vietnam, Cambodia, Laos, Thailand, Myanmar, and peninsular Malaysia. Together, these nations form the mainland of Southeast Asia, as distinct from the island nations like Indonesia and the Philippines. Today, academics and diplomats often prefer the term “Mainland Southeast Asia” over “Indochina” because it avoids colonial baggage and more accurately reflects the region’s identity on its own terms.
The combined population of these mainland nations is enormous. Vietnam alone has roughly 101 million people. Thailand has about 72 million, Myanmar around 55 million, Cambodia about 17.6 million, and Laos nearly 7.8 million. These countries are all members of ASEAN, the regional economic and political bloc, and their economies have been among the fastest growing in Asia over the past two decades.
French Indochina: The Colonial Meaning
When most people encounter the word “Indochina” in books, films, or history classes, it usually refers to French Indochina, the colonial territory France controlled from 1887 to 1954. After roughly 26 years of military campaigns and treaties, France consolidated Vietnam and Cambodia into a single administrative unit in 1887. Laos was added in 1893.
Vietnam itself was divided into three separate regions under French rule: Tonkin in the north, Annam in the center, and Cochinchina in the south. Each had a slightly different administrative status. Cambodia and Laos were treated as protectorates. The French used the label “Indochine” for the whole package, borrowing the geographic term and giving it a political meaning it hadn’t originally carried.
French colonial rule ended after the First Indochina War, which culminated in France’s defeat at Dien Bien Phu in 1954. The Geneva Accords that followed split Vietnam into North and South, setting the stage for the Second Indochina War, known in the United States simply as the Vietnam War. That conflict expanded into Cambodia and Laos as well, which is why the term “Indochina Wars” covers the entire sequence of fighting across all three countries from the 1940s through 1975.
Religion and Culture Across the Region
Theravada Buddhism is the dominant religion in Thailand, Cambodia, Laos, and Myanmar. Monks in saffron robes, temple complexes, and daily alms-giving rituals are visible everywhere in these countries. Vietnam is the outlier on the mainland: its religious landscape is shaped more by Mahayana Buddhism, Confucianism, and Taoism, reflecting centuries of Chinese political and cultural influence.
This split is part of what originally inspired the “Indochina” label. The western and central parts of the peninsula absorbed Indian religious and artistic traditions through centuries of trade and the spread of Hinduism and Buddhism from the Indian subcontinent. The Khmer Empire, which built Angkor Wat in present-day Cambodia, is one of the most dramatic examples of this Indian cultural influence. Vietnam, by contrast, spent over a thousand years under direct Chinese rule and adopted Chinese-style governance, civil service exams, and literary traditions. The region’s cultural reality was always far more complex than a simple east-west divide, but that basic pattern of Indian-influenced west and Chinese-influenced east is real enough to have given the peninsula its name.
The Region Today
Economically, the Indochinese countries are on different trajectories. Vietnam and Cambodia have been among the fastest-growing economies in Southeast Asia, with the Asian Development Bank projecting them near the top of the region’s growth charts for 2024. Thailand has a more mature, diversified economy. Laos and Myanmar, the poorest members of ASEAN, appear to have settled into a lower growth trend since the pandemic, not fully recovering their pre-2019 momentum.
Vietnam’s economy in particular has transformed dramatically since the country adopted market reforms in the 1980s. It is now a major manufacturing hub for electronics and textiles, with a population that surpasses 100 million. Cambodia has grown rapidly through garment exports and tourism centered on the Angkor temple complex. Laos remains more rural and less industrialized, with hydropower dams on the Mekong River serving as a major source of revenue.
The term “Indochina” still appears in historical writing, travel guides, and geopolitical analysis, but it carries different weight depending on context. When referring to the French colonial period or the wars of the mid-twentieth century, it almost always means Vietnam, Cambodia, and Laos. When used as a purely geographic label, it covers the entire mainland peninsula. In diplomatic and academic settings, “Mainland Southeast Asia” has largely replaced it.