February was chosen primarily because the second week of the month coincides with the birthdays of both Abraham Lincoln and Frederick Douglass. Lincoln was influential in the emancipation of slaves, and Douglass, a former slave, was a prominent leader in the abolitionist movement, which fought to end slavery.
Lincoln and Douglass were each born in the second week of February, so it was traditionally a time when African Americans would hold celebrations in honor of emancipation, Kaplan said. (Douglass' exact date of birth wasn't recorded, but he came to celebrate it on Feb. 14.)
Thus, Woodson created Negro History Week around the two birthdays as a way of "commemorating the black past," according to ASALH.
Forty years after Ford formally recognized Black History Month, it was Barack Obama, the nation's first Black president, who delivered a message of his own from the White House, a place built by slaves.
https://www.blackhistorymonth.gov/index.html