From contributions dating way back to the British colonial era, the Sikh community have played an important role in the development of the country and they are a crucial aspect of Malaysia's racially diverse setting, says Perak Ruler Sultan Nazrin Muizzuddin Shah.br br Sultan Nazrin said this during the book launch of "Sikhs in Malaysia: A Comprehensive History" by Dr Ranjit Singh Malhi on Saturday (April 10).