Typical racism. Give the black man the shortest month of the year. Were all the 31 month days already taken? :-)
What people forget is that a black scholar started the idea of "Negro History Week" and chose the period in February which included Lincoln's birthday and Frederick Douglass' supposed birthday. That later got expended to a month--but no white people were involved in selecting February.
Of course there is also January which has become Martin Luther King, Jr., Month, so it's more like 59 or 60 days (minus the first few days of January which are devoted to football games).
Frederick Douglass complained that he didn't know his own birthday because he was born a slave and his mother died when he was young. I think he decided to pick a day to celebrate--and took a day half-way between Lincoln's birthday and Washington's birthday.