Black History was first celebrated in the United States as "Negro History Week," on February 12, 1926. Carter G. Woodson, a pre-eminent historian and the founder of the Association for the Study of Negro Life and History created the week out of concern that the contributions and history of African Americans were being overlooked in the study of American history.
February was selected because it included the birthdays of both Abraham Lincoln (February 12) and Frederick Douglas (February 14), both of whom had significant impacts on the lives of Black men and women in the United States. In 1976, the week became a month long celebration.
The Association for the Study of African American Life & History declared the 2023 theme for Black History as "Black Resistance" https://asalh.org/black-history-themes/
