Oh, i thought like you used name "Bhagath singh" so you might have read alot about it.His real uncle claims that he turned very religious last days of his, and its also evident by one pic of his in Jail, which shows him with Grown hairs as in sikh religious tradition. But world over he was projected Atheist.
Anyhow, i believe a person could be very very religious and very very patriotic at same time. It has been supported by some events in history too.