History of science in the first half of the 19th century:
General state of the art:
Western Europe: Railroad, photography, microphone, gas lighting, modern cement, sewing machine, bicycle, vulcanized rubber, hygiene in medicine invented. France makes progresses in archeology.
Russian lands: Many chemical elements discovered.
Islamic World: A Persian astronomer discovers Neptune.
India: Quite some new mathematical ideas in Kerala (again). Sorry for missing details.
China: After the first Ming emperor made China adapt state-of-the-art European technology, under his successors science stagnates again - a big problem, since the development in Europe is now going faster than ever.
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And now a big retcon for West Africa (I just wanted some kingdoms gain the upper hand here, but then I simulated the whole history of conquest. If it's too long for you, just look at the map at the end of the post. MEJ should be happy - I guess there never wasn't that much AH about Africa, except Draka and Egypt):
Early 1700s: After the defeat of the Portuguese makes the waters of West Africa safer for Muslims ships, Songhay sends ships to the Kongo kingdoms, starting trade and cultural exchange.
1712: Joao de Gouveia, son of a fled Portuguese nobleman and his African mistress, becomes self-proclaimed king of the Ijaw people in the Niger delta.
1717: Sherbro people (coast of OTL Sierra Leone) united.
1721: Kingdom of Lomé (OTL Togo) established.
1722: Joao de Gouveia conquers the Ibibio people.
1724: Kingdom of Kamsar (OTL Guinea) established.
1727: Kingdom of Douala (OTL Cameroon) established.
1728: João de Gouveia killed, but he has a precedence set.
1730: Kingdom of Dida (OTL Ivory Coast) established.
1732: Kingdom of Ibo (OTL South Nigeria) established.
1733-36: Spain and Songhay fight a war. The Songhay have to fight with outdated weapons, but their numerical superiority and the hard climate give them victory. France also helps them with advisors and selling modern weapons.
1734: Kingdom of Sekondi-Takoradi (OTL Ghana) established.
1736: Kingdom of Bafatá (OTL Guinea-Bissau) established. Gouveia's kingdom falls apart, as the Ibibio people become independent.
1737: Raymundo Pires takes power of the Krou people (OTL SW Ivory Coast - he is half Krou), goes on conquering the Neyo, Bakwe and Godie people in the next years.
1738: Kingdom of Lomé extends north, along the Mono river.
1739: Sherbro kingdom attacks Portuguese stronghold on Bonthe. Portuguese ask Mende people north of Sherbro for help, who defeat the latter, but are thought by the Portuguese to become too dangerous themselves, so they support the Temne people, who'll fight the Mende.
1740: Ibibio people conquer the Ekoi.
Ewe kingdom of Abomey in OTL S Benin established.
1741: Kingdom of Yaoundé (OTL Cameroon) established.
José Damiano takes Accra, expands north, where he meets the resistance of the Ashanti.
1742: Kingdom of Labé (OTL Guinea) established.
1743: Kingdom of Igbira (OTL Nigeria) established. At the site where the Benue river meets Niger river, it becomes strategically very important.
Kingdom of Abe (OTL Ivory Coast) established, which soon also conquers the Akie.
1744: Abomey kingdom expands north, along Oueme river.
1745: Kingdom of Gbarnga (OTL Liberia) established.
Kingdom of Limba (OTL Sierra Leone) established.
1746: Raymundo Pires loses a border war against the Malinke people, after having conquered the We, who become independent again.
Kingdom of Sokodé (OTL Togo) established.
Temne-Mende war ends.
1747: After being theatened by Raymundo Pires, Gouro people make another adventurer king.
Kingdom of Agno (OTL Ivory Coast) established.
Igbira allies with Nupe against native Yoruba kingdoms.
1748: Kingdom of Tiv (OTL Nigeria, east of Igbira) established.
Raymundo Pires dies, non-Krou secede again.
1749: Kingdom of Ho (OTL Ghana, east bank of Volta river) established.
Abomey kingdom takes Savé.
1750: Kingdom of Baoule (OTL Ivory Coast) established.
Kingdom of Jukun (OTL Nigeria) established.
1751: Igbira attacked by Idoma, but can defend successfully.
Kingdom of Macenta (OTL Guinea) established.
1752: Idoma attack Igbira again, this time with the help of Igala, but again without success.
Kingdom of Suyani (OTL Ghana) established.
1753: Sokodé and Abomey kingdoms clash.
Kingdom of Ngaoundérè (OTL Cameroon) established.
1754: We defend against attack of Gbarnga.
Kingdom of Toura and Dan (OTL Ivory Coast) established.
1755: After allying with the kingdom of Tiv, Idoma and Igala beat Igbira, but leave after getting tribute paid.
Kingdom of Gwari (OTL Nigeria) established.
1756: Igbira kingdom builds the fortress of Lokoja, which controlls the place where the Benue river meets Niger river. Thus, Songhay is cut off from the sea and has to pay a toll.
Kingdom of Senoufo (OTL Ivory Coast) established.
Baoule clashes with Gouro.
1757: Igbira denies paying tribute, coalition of Tiv, Idoma and Igbala defeated before Lokoja.
Kingdom of Tamale (OTL Ghana) established.
1758: Kingdom of Koranko (OTL Sierra Leone) established.
Ashanti defeat against attack of Ho and Accra kingdoms, hold the line of Pra river.
1759: Igbira attacked by the coalition again, but defends with success.
Kingdom of Borim (OTL Nigeria) established.
Bete conquer Bakwe.
1760: Kingdom of Bertoua (OTL Cameroon) established.
Border clash of Labé with Songhay.
1761: Kingdom of Koulango (OTL Ivory Coast) established.
Malinke fight against Senoufo.
War between Yaounde and Douala.
1762: Kingdom of Bauchi (OTL Nigeria) established.
Akie (OTL Ivory Coast) conquered and divided between Abe and Agno.
1763: Igbira conquers Igala.
Kingdom of Garoua (OTL Cameroon) established.
Kingdom of Dioula (OTL Ivory Coast) established.
1764: Kingdom of Margi (OTL Nigeria) established.
Dida conquers Godie.
Songhay defeats Macente, forces them to pay tribute.
1765: Kingdom of Kono (OTL Sierra Leone) established.
Tiv conquer Bamenda (OTL Cameroon).
1766: Kingdom of Loba (OTL Ivory Coast) established.
Krou conquer Neyo again.
Malinke fight against Toura and Dan.
1767: Kingdom of Wa (OTL Ghana) established.
Baoule conquers Gouro.
1768: Kingdom of Kamberi (OTL Nigeria) established.
Igbira conquers their old enemy, Idoma.
Dida conquered by Abe.
1769: Kingdom of Maroua (OTL Cameroon) established.
Kono-Koranko War.
1770: Kingdom of Kanuri (OTL Nigeria) established.
Bafatá conquers Labé.
Ashanti defeat Sunyani, get tribute.
1771-73: Costly war between Malinke and Senoufo.
1772: Kingdom of Tenkodogo (OTL Burkina Faso) established.
Temne conquer Koranko.
1774: Yoruba make border war against Edo.
1775: Kingdom of Dedougou (OTL Burkina Faso) established.
Lomé conquers Sokodé.
1776: Temne conquer Kono.
1778: Baoule conquers Senoufo.
1781: Songhay conquers Gwari.
1782: Songhay attacks Igbira, besieges Lokoja. Idoma become independent again.
1783: Songhay retreats, when uprisings in other provinces begin.
1786: Igbira reconquers Idoma.
1788: Jukun and Songhay divide Bauchi.
1792: British troops land in Australia (OTL South Africa). They storm several cities and fortresses of the Söderlinger, but have to give them back after the end of the war.
Kamsar attacks Temne, but are beaten back.
1795-97: Yoruba make war against Igbira, but the latter again defend successfully. Uprisings of Idoma defeated.
1796: Temne conquer Limba.
1800: Dioula conquered by Baoule.
Early 1800s: Ashanti expand north, to Black Volta river.
1804: Igbira unite with Nupe.
1809: Wa conquer Loba.
1811: Ashanti conquer Sekondi-Takoradi.
1815: Igbira conquer Ibo.
1817: Baoule conquer Agno with Abe help.
1820: Ho conquered by Lomé.
1824: Igbira conquer Tiv, with help by Douala, which gets Bamenda.
1827: Baoule conquer Dida, get a harbor.
1831/32: Ashanti attack Accra, reduce it to the area around the capital.
1836: Douala conquers Yaoundé.
1839/40: Igbira conquer Gwari and Borim.
Legend of the map:
B. = Bafata
Tem. = Temne
Mal. = Malinke
Ash. = Ashanti
L. = Lomé
A. = Abomey
Yor. = Yoruba kingdoms
Kan. = Kanuri
Dou. = Douala
The thin green line marks the southern border of Songhay. The blue lands are under direct control of Portuguese traders (yes, mostly slave traders).
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