The International Engineering Public Company Limited (IEC) was established in 1922 to undertake engineering work on the Bangkok-Aranyaprathet Railway connecting Thailand to the Cambodian border for the first time. IEC took a position at the forefront of Thai engineering and technology through its cooperation with 'Caterpillar' the world's number one tractor producer, introducing tractors to play an important role in national development.
IEC helped build the foundation for the country's rapid economic development by introducing electrical appliances such as radios, televisions, refrigerators and washing machines to promote a better quality of life. The company provided public utilities such as electrical engineering systems as well as expanded its operations to vessel transportation and communications businesses, which served to boost the company's growing reputation and success. In 1929, IEC became the sole official distributor of 'Westinghouse' products.
In the aftermath of the Second World War, the company was involved in the recovery of many engineering and communications projects. This era was regarded as the golden age for IEC and Thai telecommunications development. In 1965, as a result of its role in national development, IEC became one of the first Thai companies to attain the honor of 'Royal Appointment' from His Majesty the King.
Due to IEC's dedication to introducing new technology into the Thai market, in the early 80's the company began to see the potential of the telecommunications market, and was the first importer of Nokia telephones into Thailand. During IEC's tenure as official distributor for Nokia, the company helped to establish the Nokia brand.