"Straits" refers to the "Straits Settlements" of the British East India Company East India Company which comprised Penang, and Malacca in present day Malaysia a

"Straits" refers to the "Straits Settlements" of the British East India Company East India Company which comprised Penang, and Malacca in present day Malaysia and also present day Singapore. And "Chinese" here refers to ethnic Chinese not necessarily Chinese speakers, nor did the OP imply they were Chinese speakers.