1. Bhagat Singh was among other Indians who admired Karl Marx's vision which applies to the entire humanity. So it doesn't matter that Marx was not Indian.
But that doesn't make him him a noticeable personality in India.
2. The Communist Party of India was founded in 1920. BJP was founded in 1980, six decades after the foundation of the CPI.
Hinduism is the oldest ideology of the earth so everybody on this planet should hail and celebrate Hindu festivals. What say?