On the eve of the french revolution, New France was divided into 4 parts:
- The Principality of Louisianna: The Apanage of the Prince of Louisianna.
- The Royal Province of New Francy: Directly controlled by the French Royal Domain.
- The Highlands: Nominally under the control of the Lieutenant-General of New-France but de facto administered by various military officers, chartered companies' representatives and allied native tribes. The power of the first two groups only extended to the area immediatly surrounding their forts and counters.
- The Maritime Province of the Saint-Lawrence Islands: Comprising the islands in the Gulf of Saint-Lawrence and some coastal posts. Administered by the French Royal Navy.
Of all the Saint-Lawrence Islands, Saint-Pierre-And-Miquelon [SPeM afterward] had been semi-permanently inhabited the longest, at least since the 15th century. The fishermen that visited it (mainly Basques) where finaly able to enjoy a bit more comfort and protection when the French Government decided in the 17th century to set up a small fort on Saint-Pierre Island. Thanks to its stores, the fishing fleet could reduce the amount of provision it needed to carry and thus, bring back more fish. Some fishermen even began settling near the fort year-round.
After the execution of the King in 1792, both Louisianna and the Saint-Lawrence Islands sided with the Republicans against New Francy and the Monarchists. Fearing that the Islands might be used as a jumping-off point for the invasion of its territory, New Francy sent out its small fleet to occupy them. After taking control of Anticosti and the Magdalenes, the expeditionary corps found itself stretched to the limit and unable to move on to SPeM and the islands off the coast of Alba Nuadh.
Since the Scots shared the Neofrancians' worries in regard to France, a deal was struck for the former to occupy the islands for the duration. Decades later, as part of the Treaty of Vienna, France agreed to recognise the aquisition of previously French territories in North America by European powers. To protect its fishing interests however, France demanded the return of SPeM.
New Francy objected to Scotland for permanently settling St-John and Royal Islands and letting the Republicans re-occupy SPeM but after some negotiation, New Francy agreed to renounce its claims on the islands in return for control of the Acadian peninsula contiguous to its borders.
Because neither France nor New Francy officialy recognised one another, both sides continued to deny the other side's claim to the former maritime province's islands. It quickly escalated into naval warfare as both sides sent armed escorts to protect fishing boats off the coast of Mueva Sepharad. The Magdalenes and SPeM became fortified bases from which privateers and naval warships would go raiding the other side. 
With the fall of the empire and the royal restoration, New Francy began negotiation to rejoin France. This meant an end to the naval warfare in the Gulf of Saint-Lawrence and for the first time in a generation, a regular ferry service was opened between the islands. Unfortunatly, the negotiations were unsuccessful and tensions rose once more. With the final end to the restoration, New Francy and France returned to an official state of war, although the truce was maintained, and no privateers' licences were ever issued afterward. Despite the odd incidents, the de facto ceasefire has been maintained to this day, and while a full complement of troops and warships is being kept on the islands, to be transfered to SPeM is considered one of the most boring assignement in the French navy. 
After the territorial reorganisation that followed the declaration of the Renewed Republic, SPeM gained the status of "Departemental Community". This meant that the islands enjoyed at the same time the right of a prefecture, a department and (to a lesser extent) a community. Among other things, this mean that that they elect their own prefect and have been allowed to pass legislation giving basque (the common language of the permanent inhabitants) the same status as Francian and Narbonosc on the islands.
1- This was more or less the de facto situation *here* although it never realy existed as a well defined entity.
2- This province never existed *here* but its components did belong to France (under the jurisdiction of either Canada, Acadia or Plaisance). It's existence *there* help explain a few oddities.
3- *here* Napoleon planed eventualy to regain some of the lost North-American lands. Assuming the same *there*, recognising the *european* aquisitions would have placated potential enemies while leaving him free hands to invade Louisianna and New Francy by way of Hayti (recognised back then *there* as a kingdom within the Napoleonic Empire).
4- Obviously didn't happen *here* but France and Canada have had over the years many disputes in regard to territorial fishing rights. Since *there* the 2 governments involved don't even recognise one another, the disputes would have been a bit more acerbic.
5- My vision of this is akin to *here* being a soldier of one of the occupying powers serving in Germany near the end of the Cold War. Lots of drill but mostly boredom intersped with a few tense moments of invasion warnings on the sonar that later prove to be only a group of frolicking humpback wales.