The USS Angelou was a Federation starship operated by Starfleet in the 23rd century.
Hemmer served on the Angelou prior to his time on the USS Enterprise. For Starfleet Remembrance Day in 2259, he wore a pin memorializing the crewmates he had lost from this ship. (SNW: "Memento Mori")
This ship was presumably named after American poet and civil rights activist Maya Angelou.