The Saints and Marie Galante are significant to Wide Sargasso Sea because of the battle between the French (who were working with the Spanish) and the English that happened in the seas between them. Looking into the battle can provide context on Antoinette's relationship with the unnamed husband. According to Britannica, "in concert with a Spanish fleet... the French planned an attack on British-owned Jamaica... a British fleet, under Admiral Sir George Rodney, was sent to block the move". This battle can be viewed as a metaphor for Antoinette and the unnamed husband's relationship at the time. Antoinette drugging her husband and assaulting him on page 82 of Wide Sargasso Sea can be interpreted as the French's attack (with the help of the Spanish, which would be Christophine). The unnamed husband then went on to confront Antoinette and Christophine. Britannica goes on to state that "the engagement began with the two fleets sailing parallel to one another in line of battle.... Rodney exploited a shift in the wind and, breaking formation against the prevailing naval strategy of the era, cut across the line, raking the French ships on either side with his broadsides. Other British ships imitated their commander, and the French line fell into disarray." This reflects the unnamed husband's reaction to Christophine. He wasn't able to trap her and Antoinette through traditional means (sending them to jail), so he decided to get Antoinette locked in the attic instead. He won through an unconventional means. What's interesting is that the success of Rodney's move (as mentioned in a footnote on page 101 of Wide Sargasso Sea) was seen as saving Jamaica. That implies that unnamed husband removing himself and other harmful people associated with colonialism (like his wife) from Jamaica to win that fight with her impacted those around him positively.
This information comes from Britannica and Wide Sargasso Sea.
This location illustrates colonization and empire because it shows how colonization impacts the novel. The fight was between colonial forces and was long before the novel takes place. However, it is still mentioned in the novel and still impacts how the novel is read. Mapping it shows how far colonial forces spread and how they continue to impact people's perceptions of a place for centuries after colonialization ended.
Mapping this location on COVE reveals how the history behind this location complicates or depends the novel's plot by comparing this historical moment to the unnamed husband's actions.
Research: https://editions.covecollective.org/node/23739/edit
Image: https://en.wikipedia.org/wiki/Îles_des_Saintes
Page Location is Mentioned in Wide Sargasso Sea: page 101