Malaysian Tamil, Malaysia and Indonesia's former common language, was recorded to have been used in Sumatran and Malay Peninsula trading as their commercial activities continued in the 15th and 19th centuries.
Hamilton record that Tamil was the common language of commerce in Malaysia and Indonesia during historical times. The maritime Tamil significance in Sumatran and Malay Peninsula trading continued for centuries and borrowings into Malay from Tamil increased between the 15th and 19th centuries due to their commercial activities. 
