Answer:
McKay's poem is about his desire to return to his homeland, in Jamaica, which he left to go to America in 1912. This information can only be known by knowing McKay's personal background. However, the poem itself is clearly about someone who longs to go back to their homeland.
Explanation:
The repetition of "I shall return" shows the desire to go back to a place where the author has already been at. His reference to the 'hidden depths of native life' show he has a connection with a native community. The idea of 'dim remembered runes' shows that there´s a cultural knowledge that remains which the author wants to rediscover.
Finally, the last sentence describes the reason to go back: 'To ease my mind of long, long years of pain', which we can infer refers to the sadness that comes with being an exile.
