When the changes caused from the POD in 1200 started to affect the lands of the Welfs (in the second half of the 13th century), Braunschweig was divided between two lines: Lüneburg in the North, and Braunschweig proper in the South. The latter line would be object to many splits and reunifications (see below).
During 1304-1309, the Braunschweig War happened between Otto II the Just of Lüneburg and Albrecht II of Göttingen, who is said to be vying for the heritage of his five nephews.
An important decision that would change the world happened in 1460 when the ambitious duke Bernhard I of Braunschweig-Lüneburg, who had inherited the biggest land of the Welfs, founded a colony in Atlantis at the site of OTL Philadelphia, called Martinsburg (with the help of the Hanseatic League cities Hamburg and Bremen).
In the years 1475-95 many Germans fleeing from the Twenty-Year War in the HRE, and especially from the religious fanatics ruling in Münster, went to the colonies of Braunschweig (and the Netherlands, too). Braunschweig-Lüneburg itself however acquired the former clerical lands of Bremen and Verden (thus gaining access to the sea), and could also acquire Hildesheim and Eichsfeld (former property of the electorate of Mainz). The city of Bremen which felt threatened by Münster now sought the protection of Braunschweig, which helped further.
The grown importance of Braunschweig became visible during the Reforms of the HRE 1500-1508, when Braunschweig-Lüneburg got the ninth electorate. Clearly they had profited from the Atlantean trade.
After the Twenty-Year War, the colonies in Atlantis developed well. In 1500, a ship from Braunschweig-Lüneburg discovered OTL Bermuda by accident. During the Great Occidental War, Braunschweig-Lüneburg claimed the islands of Martinique, Santa Lucia in 1533. And 1554, it was able to form its second province in Atlantis, called Waldstätten (OTL Pennsylvanian Appalachians). Experienced woodcutters and sawmill builders were invited there from as far as Switzerland.
In 1588, duke and elector Ernst V of Braunschweig-Lüneburg inherited the lands of the last sideline, Braunschweig-Wolfenbüttel.
Unification with Denmark
In 1628, king Kristian I of Denmark died without heirs, and the nobles decided to make old duke Ernst V their new king. Now, he reigned an empire reaching from Bergen in Norway to the Harz mountains. And in Atlantis, the German-speaking colonies were joined by new ones, when Denmark-Braunschweig first defeated the Dutch in Atlantis 1632 in the battle of Nieuw Brugge (OTL Easton, PA - later renamed Neubrück), taking Nieuw-Nederland, and 1637 used the Dissenter's Revolt in New England not only to take back the (once Danish) colonies of Haraldsborg and Anderland, but also to become protector of the Commonwealth of New England (since the dissenters preferred "the papist German king in Europe to the papist English governor in Markland").
In 1642, the colonies of Denmark-Braunschweig (Martinsburg, Waldstätten, Nieuw-Nederland, Haraldsborg and Anderland) were united under a common administration.
King Humphrey I planned to regain England's old colony in North Atlantis, after having accepted the loyalty of Markland. However, the states of Denmark-Braunschweig and Florence allied against him in the "Atlantean Coalition" and surprisingly defeated the English fleet 1652-56. New England stayed a Danish-German protectorate.
During the anti-French War Braunschweig had to fight on France's side. Although they lost, they became winners in the long run because the peace of Amsterdam gave them what had been the north of French Louisiane, which would become essential for the development of German Atlantis, since this vast space with its coal and iron resources now would be German-settled.
Denmark-Braunschweig had fought, without success, for the cause of monarchy in the first two French Republican Wars. 1790, republican France and Sweden made a secret alliance against Denmark-Braunschweig. After the third French Republican War, in the Peace of Frankfurt 1793, Braunschweig (incl. Schleswig-Holstein) became a French satellite, the Engeric Republic. 1818, it became part of united Germany after the successful German Uprising.
Lesser dynastic events
1292: Einbeck (older line) split of Grubenhagen
1309: Calenberg split of Wolfenbüttel (elder line); Heinrich II of Wolfenbüttel (elder line) goes to Göttingen
1339: Göttingen inherits Wolfenbüttel (elder line)
1353: Gehrden (older line) split of Calenberg
1359: Wolfenbüttel (middle line) split of Göttingen
1369: Einbeck (older line) inherits Lüneburg
1400: Göttingen inherits Wolfenbüttel (middle line)
1408: Gehrden (older line) inherits Lüneburg-Einbeck
1420: Wolfenbüttel (younger line) split of Göttingen; Gehrden (younger line) split of Lüneburg
1421: Lüneburg inherits Gehrden (younger line)
1423: Lüneburg inherits Calenberg
1433: Northeim split of Göttingen
1441: Lüneburg inherits Grubenhagen
1460: Einbeck (younger line) split of Lüneburg
1473: Seesen split of Göttingen
1484: Göttingen inherits Northeim
1504: Blankenburg (older line) split of Wolfenbüttel (younger line)
1516: Wolfenbüttel (younger line) inherits Blankenburg (older line)
1519: Blankenburg (younger line) split of Wolfenbüttel (younger line)
1522: Lüneburg inherits Einbeck (younger line)
1529: Lüneburg inherits Göttingen
1563: Hannover split of Lüneburg
1566: Lüneburg inherits Seesen
1571: Hannover inherits Lüneburg
1585: Wolfenbüttel (younger line) inherits Blankenburg (younger line)
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|Nations that became defunct|