Historical clue formulations

• Democratic Republic of the Congo, once — 2025-04-19
• Former name of the Democratic Republic of the Congo — 2024-11-12
• Former name of the second-largest country in Africa — 2022-10-07
• Former name of sub-Saharan Africa's largest country — 2020-08-01
• Kinshasa's country, formerly — 2020-01-28
• Rumble in the Jungle setting — 2019-12-30
• Angola's northern neighbor, once — 2019-08-08
• Where Ali won his 1974 world heavyweight title — 2018-07-19
• Site of a 1974 fight won by 40-Across — 2018-03-03
• African nation renamed in 1997 — 2016-05-18
• Former name for Congo — 2015-06-22
• 1971-97 nation name — 2014-05-09
• The Congolese franc replaced it — 2014-04-18
• Bygone country name or its currency — 2013-08-24
• Congo, once — 2013-02-04
• Congo, formerly — 2012-11-12
• Congo, from 1971 to 1997 — 2012-03-19
• Old country name or its currency, both dropped in 1997 — 2012-03-03
• Setting for the 1996 documentary "When We Were Kings" — 2012-02-04
• Former name for Congo — 2010-12-20
• 1990s war locale — 2010-02-28
• 1971-97 nation name — 2009-09-26
• Congo's name before 1997 — 2009-04-14
• Congo, once — 2009-03-11
• Where Ali dethroned Foreman — 2008-10-07
• Site of Ali's Rumble in the Jungle — 2007-10-23
• Rumble in the Jungle setting — 2007-07-07
• Congo, formerly — 2005-03-21
• Congo, once — 2003-12-31
• Country name from 1971-97 — 2003-02-07
• Congo Basin river — 2002-03-13
• Old name for Kinshasa's country — 2001-09-03
• Where Ali KO'd Foreman, 1974 — 1999-11-10
• New ___ (Congolese money) — 1999-05-15
• Former country name — 1999-01-28
• Ali-Foreman battle site — 1996-05-01
• Belgian Congo, today — 1995-08-07
• World's largest cobalt exporter — 1994-06-23
• Its capital is Kinshasa — 1994-06-03