Historical clue formulations

• Country whose capital is named after an early U.S. president — 2022-09-25
• Monrovia's land — 2022-08-30
• Africa's oldest republic — 2017-08-27
• African republic colonized by freed American slaves — 2013-04-02
• Country with modern Africa's first female head of state — 1999-08-08
• Oldest republic in Africa — 1997-03-13