In this timeline, Anne of Brittany's marriage with the Holy Roman Emperor, Maximilian I in the 1490s succeeds against objections by the French King and thus Brittany preserves its sovereignty as a Habsburg realm.

Initially, this put France in a perilous predicament now that France was geographically surrounded by Habsburg Powers, motivating them to push their claims in Northern Italy further during the Italian Wars by allying the Venetians to occupy Milan and Piedmont. Brittany would also establish a New World colony called New Armorica to send resources like furs, maize, and whaling products back to Europe. Which further secured Brittany as a regional power.

In 1588, Safe docking in Brest and Naval assistance from Brittany could lead to a successful Spanish Invasion of England and the Abolition of the Tudor Monarchy and Anglican Church, being replaced by the Catholic Spanish monarchy while Ireland was ceded to the Breton Duke. The application of the Catholic Inquisition on the English would cause great animosity, leading to a Separate English revolt under a more radical sect of Protestantism such as Calvinism, Presbyterianism, or Lutheranism with some smaller English sects possibly popping up.

With funding from the Dutch Revolt and France. It is likely that England would be able to win independence from Spain as a republic although considerably weaker than in our timeline, leaving the Dutch to be the main colonial power during the 17th/18th centuries as preoccupation of Spanish forces in England would allow the Dutch to take over cities like Antwerp and Brussels. Brittany could also occupy Wales in order to preserve Habsburg power in Britain from the English Republic leading to the development of a Pan-Celtic identity within the Breton Realm.

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