During this time, whenever the Parti Québécois won provincially, the entire eastern half of the island was coated light blue.
Prior to the rise of the Bloc, the region voted solidly Liberal for decades before being swept up in the Brian Mulroney tide, electing Quebec nationalists under the Progressive Conservative banner.
In 2011, the federalist NDP swept every seat in this region amid the surge of popular support in the province and the concurrent Bloc meltdown, in all but one case by well over 6,000 votes.
The NDP largely held its gains in 2015, losing Honoré-Mercier to the Liberals and La Pointe-de-l'Île—long reckoned as the most strongly sovereigntist riding in Quebec—to the Bloc.
In 2019, however, the NDP was cut down to just one riding in eastern Montreal, with the Bloc holding onto La Pointe-de-l'Île and the Liberals taking the other three.
Both the NDP and the Conservatives improves their results with a second place for both, achieved respectively in Laurier—Sainte-Marie in La Pointe-de-l'Île, albeit well behind the Bloc in both cases.