Prior to the foundation of Manitoba, the Lieutenant Governor of the Northwest Territories occupied a designated residence within the walls of Upper Fort Garry; a house that was, at one point, used by Louis Riel as president of the provisional government of Red River.

After the new province joined Confederation on 15 July 1870, a structure five kilometres outside of Winnipeg was leased for use as the lieutenant governor's residence, known as Silver Heights,[3] but it was found unsuitable, given its size and distance from the capital.

Year before till middle of August..."[3] Further, as the population of the province was increasing, the need for public buildings became more pressing, and a delegation travelled to Ottawa to discuss with the Queen's Privy Council for Canada the matter of parliament allocating funds for a new legislative assembly and Government House for Manitoba.

[7] The architect Frank Worthington Simon included in his plans for the Manitoba Legislative Building a new Government House, to be constructed on the bank of the Assiniboine River, opposite the parliament.

It is also where numerous vice-regal events take place, such as the bestowing of provincial awards or inductions into the Order of Manitoba, as well as luncheons, dinners, receptions, and speaking engagements.

The volume and its facade composition was at first symmetrical along an east-west axis through the centre of the building, though this arrangement was later altered by the addition of new wings; this is clad in brick, trimmed with cut stone and ornate wood cornices at the roof line, and iron cresting tops the tower.

[2] The overall design was described in 1883 as "Italian, modified to suit the requirements of the climate," though the same year an early visitor noted in the guest book: "It is an unpretending looking structure, of nondescript architecture and with no outside ornamentation."

[3] By later in the 20th century, however, provincial architects stated the house is "Victorian architecture with French influence from the Second Napoleonic Empire with the flat steep-sided Mansard roof".

Later, in 1901, a veranda was built around the north-east corner of the house, and a ballroom was added to the rear, both at the personal expense of Lieutenant Governor Daniel Hunter McMillan.