McCreary served as an alderman and the 16th Mayor of Winnipeg and as a Member of the House of Commons of Canada.
[1] He also became Commissioner of Immigration that year, noted for his assistance with providing Doukhobors with food supplies in 1898 as they settled in Western Canada.
He served most of his term in the 9th Canadian Parliament until his sudden death at Ottawa's Russell House Hotel on 4 May 1904.
A doctor and coroner examining his body concluded that McCreary died of heart disease early that morning.
He indicated to some colleagues the previous evening that he was experiencing chest pains, following his attendance in Parliament.