Donald Alexander Macdonald

{{Short description|Canadian politician}}

{{For|the Canadian general|Donald Alexander Macdonald (general)}}

{{Use Canadian English|date=September 2021}}

{{Use dmy dates|date=September 2021}}

{{Infobox officeholder

| honorific-prefix = The Honourable

| name = Donald Alexander Macdonald

| honorific-suffix = {{post-nominals|country=CAN|PC|size=100%}}

| image = DonaldAlexanderMacdonald23.jpg

| constituency_MP2 = Glengarry

| parliament2 = Canadian

| predecessor2 = Riding established

| successor2 = Archibald McNab

| term_start2 = September 20, 1867

| term_end2 = May 18, 1875

| office = Lieutenant Governor of Ontario

| order = 4th

| predecessor = John Willoughby Crawford

| successor = John Beverley Robinson

| term_start = May 18, 1875

| term_end = June 30, 1880

| monarch = Victoria

| governor_general = The Earl of Dufferin
Marquess of Lorne

| premier = Oliver Mowat

| birth_date = {{birth date|1817|2|17}}

| birth_place = St. Raphael, Upper Canada

| death_date = {{death date and age|1896|6|10|1817|2|17}}

| death_place = Montreal, Quebec, Canada

| nationality = Canadian

| spouse =

| party = Liberal

| relations = Alexander Francis Macdonald, brother
John Sandfield Macdonald, brother

| children =

| residence =

| alma_mater =

| occupation =

| profession =

| nickname =

| allegiance = Upper Canada

| branch = Canadian militia

| serviceyears = 1840s-1860s

| rank = Major
Colonel

| unit = Glengarry Militia

| commands = 4th Battalion, Glengarry Militia

| battles =

}}

Donald Alexander Macdonald {{post-nominals|country=CAN|PC}} (February 17, 1817 – June 10, 1896) was a Canadian politician.

Born in 1817 in St. Raphael's, Upper Canada, Donald Alexander Macdonald studied at St Raphael's College under the first Catholic Bishop of Ontario, Alexander Macdonell. He became a railway contractor and was elected as a member of the Legislative Assembly of the Province of Canada from 1857 to 1867. He was the Liberal Member of Parliament for Glengarry in the House of Commons of Canada from 1867 to 1875, and served as Postmaster General of Canada. In 1875 Macdonald was appointed the fourth Lieutenant Governor of Ontario and held that post until 1880. He died in Montreal in 1896.

Macdonald served as a Major in the 4th Battalion, Glengarry Militia, succeeding his brother John as Commanding Officer in 1852.{{cite book |last=Patterson |first=B.Gen. W.J. |author-link= |date=1995 |title=Up The Glens: Stormont, Dundas, and Glengarry Highlanders 1784-1994 |url= |location=Cornwall |publisher=Old Book Store Publishing |page=33 |isbn=}}

He was the brother of John Sandfield Macdonald, the first Premier of Ontario, and Alexander Francis Macdonald, the MP for Cornwall from 1874 to 1878.