Mexico abolished slavery in 1829, and united with Colombia in encouraging Cuba to throw off the Spanish yoke, abolish slavery, and join the sisterhood of New World republics.

This led to an effective protest on the part of the United States.

Both Spain and Mexico were advised that the United States could not with safety to its own interests permit the emancipation of slaves in the island of Cuba.

But with the British Emancipation Act of 1833, Cuba became the only neighboring territory in which slavery was legal.

These acts of emancipation added zeal to the determination of the Southern planters to secure territory for the indefinite extension of slavery to the southwest.