Nations of Insular Southeast Asia

Insular Southeast Asia (Maritime Southeast Asia) comprises the island nations between the Indian and Pacific Oceans:

• Indonesia – world's largest archipelago (17,000+ islands).
• Philippines – 7,600+ islands.
• Malaysia – Peninsular Malaysia + East Malaysia (Borneo).
• Brunei – small sultanate on Borneo.
• Singapore – city-state island at Malacca Strait.
• East Timor (Timor-Leste) – eastern half of Timor island.

Contrast

Mainland Southeast Asia (Vietnam, Thailand, Myanmar, Laos, Cambodia) lies on the continental peninsula.

Shared Traits

• Austronesian linguistic roots.
• Maritime trade history (Srivijaya, Majapahit, Malacca).
• Tropical rainforest/climate, coral reefs, volcanic geology.
• ASEAN membership (all six).