What is the main theme of poem A Sea chantey by derek walcott?

In "A Sea Chantey", Derek Walcott explores themes of nostalgia, cultural roots, and the enduring connection between individuals and their ancestral heritage. This is evident in how he draws parallels between the historical experience of the African diaspora and the lives of contemporary Caribbean sailors. While it delves into the pain and loss associated with history, the poem ultimately conveys a message of perseverance, celebrating the spirit of community and resilience amongst those descended from a lineage of seafarers.