[6] During the immigration boom of the early 20th century, the Ocean Limited and other passenger trains on its route saw increased use as they provided key wintertime connections for both the Grand Trunk Railway and Canadian Pacific Railway in moving sponsored immigrants to lands in the Prairie provinces.

In April 1978 this division was split off as a separate Crown corporation named Via Rail Canada, taking with it all CN passenger trains and equipment.

Under Via, the Ocean underwent several changes in its operation: The route taken by the Ocean runs through eastern Canada including the Island of Montreal and the city's skyline and suburbs, the lower St. Lawrence River valley, the Matapédia River valley, the south shore of Chaleur Bay and the forests of eastern New Brunswick, the Tantramar Marshes, the Cobequid Mountains and Wentworth Valley, the edge of Cobequid Bay and mixed farmland through central Nova Scotia to Halifax.

Three Renaissance train-sets supported the Ocean route, but the reduction to three departures in each direction per week in late 2012 reduced the need to only two sets of equipment.

The Ocean is almost invariably hauled by a pair of London, Ontario-built GM F40PH locomotives, all of which CAD Railway Industries of Montreal has upgraded to the F40PH-3 model.

These runs have been popular with railfans and the travelling public, as they provide more types of sleeping accommodations, a dome accessible to coach passengers, and a full dining car with meals cooked on board (a contrast to the catered meals in the normal Renaissance dining cars).

The balloon track at Halifax used to turn locomotives and passenger cars located in the Port of Halifax's South End Container Terminal was taken out of service in late 2020 to create more storage space for containers and the balloon tracks were severed in the fall of 2021.