The poem contains allusions to literature and historical events related to the oppression of Black Americans.
The most prominent allusion in the poem is the "caged bird" itself, which Angelou borrows from an earlier poet, Paul Laurence Dunbar. In his poem "Sympathy," Dunbar compares his experience as a Black man to that of a bird in captivity, writing:
I know why the caged bird sings, ah me,
When his wing is bruised and his bosom sore,—
When he beats his bars and he would be free;
It is not a carol of joy or glee,
But a prayer that he sends from his heart’s deep core
Angelou's poem clearly builds off of Dunbar's ideas. Dunbar's "Sympathy" was published in 1889, while Angelou's poem was written almost ninety years later, in 1983. By alluding so clearly to Dunbar's poem, Angelou's poem both pays homage to an earlier Black American poet, while also making the forceful argument that the image of the caged bird is still relevant, and by extension, that the racism the cage symbolizes is still alive and well.
The poem also makes an allusion to the slave trade of the 17th, 18th, and early 19th centuries when it mentions the "trade winds" in line 24. The importation of slaves to the United States was part of a larger Triangular Trade, in which:
- Sugar, tobacco, and raw cotton were shipped from the United States to Europe
- Textiles, rum, and other manufactured goods were brought to Africa
- Slaves were brought to America
These trade routes were significantly influenced by the trade winds, which blow east to west from Africa toward the Caribbean. The reference to the "free bird" thinking of the "trade winds" is part of what makes it clear that the free bird symbolizes white America, which sees its freedom as justifying the exploitation of the rest of the world (or, as the poem puts it, "dar[ing] to claim the sky.")
Finally, the caged bird's song itself is likely an allusion to spirituals, which were created and sung by enslaved Black communities and often expressed a longing for freedom, much like the song of the caged bird. Many people defended slavery by arguing that such spirituals were expressions of joy that implied that slaves were happy with their lot. The poem—building on a tradition of pushback against this racist idea among Black Americans, including Frederick Douglas and Paul Lawrence Dunbar—makes clear that such songs arose not as expressions of joy, but rather of pain. These songs did not justify slavery or other racist oppression, but condemned it.
The bird's song can also be read as an allusion to poetry—specifically to this poem and more generally to the speaker's desire to write poetry. Just as the enslaved Black community expressed longing in their spirituals, so too has the speaker found a way to express their caged life through poetry.