Ranong, once a small vassal town of Chumphon during the Ayutthaya period, later gained importance due to its abundant natural resources, particularly tin. Known as "Mueang Ranong" (City of Tin), Ranong was initially governed by local leaders with the title "Luang Ranong." In the early Rattanakosin period, a Chinese immigrant named Khaw Soo Cheang obtained the right to collect tin taxes in Ranong and nearby areas, eventually being appointed as Luang Rattanachetsiri, head of tin revenue for both Ranong and the neighboring Mueang Tra.

Due to Ranong's strategic location near British-occupied Burma, King Rama IV elevated Ranong and Tra to independent administrative districts, granting Khaw Soo Cheang the title Phraya Rattanachetsiri in 1862. His efforts in managing tin resources brought economic prosperity to the area. During King Rama V’s reign, Ranong gained independence from Chumphon's jurisdiction, and Mueang Tra was later reorganized as Kra Buri District under Ranong Province.

Key Historical Roles of Ranong:

  1. The City of Tin Ranong was known for its rich deposits of tin, also referred to as "black lead." It played a major role in Thailand's economy, with tin mining being the primary industry. Ranong became the first town in Thailand where the local mining leader received a noble title, marking its importance in national economic development.
  2. Border City Following the cession of the cities of Mergui and Tenasserim to the British, the Kra Buri River was established as the boundary between Thailand and British Burma in 1899. This positioned Ranong as a critical border city and a trading hub with British-controlled Burma. Economic interactions between Thailand and Burma continued to bring prosperity to both sides of the border, which persists to this day.
  3. Kra Isthmus The Kra Isthmus, the narrowest part of the Malay Peninsula at about 44 kilometers across, lies near Ranong. Historically significant as a potential site for a canal linking the Andaman Sea and the Gulf of Thailand, the Kra Canal proposal was explored by King Rama IV as a means to facilitate faster shipping routes between Europe and China. However, due to British objections over potential impacts on their regional interests in Penang and Singapore, the canal project was ultimately abandoned. The Kra Isthmus remains a point of interest for economic and strategic studies in Thailand.
  4. Royal Residence Ranong has long served as a royal destination. King Rama V first stayed in Ranong in 1890, residing at the Rattanarangsan Throne Hall on Niwet Khiri Hill. Successive Thai kings, including King Vajiravudh (Rama VI) and King Prajadhipok (Rama VII), also stayed in Ranong. In 1959, King Bhumibol Adulyadej and Queen Sirikit visited the province, and in 1988, Princess Maha Chakri Sirindhorn also made an official visit.