Toensing and The Fifteenth Legislature of Minnesota, 1873 list his birth year as 1836; the Biographical Directory of the U.S. Congress and Progressive Men of Minnesota, 1897 both list 1838.
Toensing and the Minnesota Legislative Manual, 1869 list his last name as McDonald. The Biographical Directory of the U.S. Congress, and The Fifteenth Legislature of Minnesota, 1873 list MacDonald. Minnesota in Three Centuries, Progressive Men of Minnesota, 1897; and the Minnesota Legislative Manuals, 1875, and 1876 list Macdonald. The Minnesota Legislative Manuals, 1871, 1873 and 1874 list both McDonald and MacDonald. The Minnesota Legislative Manual, 1870 lists both MacDonald and Macdonald.
He moved from Scotland to Nova Scotia, Canada, with his parents. He came to the United States in 1846. They moved to Pittsburgh, Pennsylvania in 1847. He then moved to St. Paul, Minnesota in spring 1855. He came to Belle Plaine, Minnesota in fall 1855. He moved to Shakopee, Minnesota in 1861.
"Although he has always been affiliated with the Democratic party, he maintains a high degree of independence in his political beliefs, and at present regards himself as an independent in politics." (Progressive Men of Minnesota, 1897)
He "joined the People's Party in 1892, and afterwards served as chairman of the state central committee of that organization." (Progressive Men of Minnesota, 1897)
He ran unsuccessfully as the Democratic party endorsed candidate for Minnesota Attorney General in the 1872 election.
He ran unsuccessfully as the Democratic party endorsed candidate for reelection to the United States House of Representatives in the 1888 election.
"Another prominent Democrat was John Louis Macdonald." (Twelfth State Legislature. Minnesota in Three Centuries, 1908, p. 37)
He died from injuries related to a streetcar accident in Kansas City, Missouri. He was buried at St. Mary’s Cemetery in Kansas City, Missouri.