William M. Blair

William McCormick Blair (May 2, 1884 – March 29, 1982), was an American financier.

William McCormick Blair was born May 2, 1884 in Chicago. His father, Edward Tyler Blair, was the son of William Blair, who founded the first wholesale hardware house in Chicago. Edward was a Yale graduate in 1879, who wrote several books including a history of the Chicago Club, and spent his life working in his father's firm. He was very wealthy, and employed four Swedish servants to manage the house while his children were growing up.

William McCormick Blair's mother, Anna Reubenia "Ruby" McCormick (1860–1917), was the daughter of the agricultural machinery manufacturer William Sanderson McCormick (1815–1865) and a member of the illustrious McCormick family. Her grandfather was Robert McCormick (1780–1846), who invented a mechanical reaper.

William graduated from Groton School in 1903, and received a BA from Yale University in 1907. At Yale, he was on the rowing crew and a member of the Skull and Bones society. He later received honorary degrees from Northwestern University in 1964 and Lake Forest College.

Upon graduation he entered the Northern Trust Company of Chicago. Shortly after, he entered the bond brokerage firm, David Reid & Company. In 1909 he moved to Lee, Higginson and rose through the ranks, becoming managing partner of its Chicago office.

When it looked as if America would enter World War I in 1917, Blair was involved with the Four-Minute Men of Chicago, giving speeches during film intermissions. He was also active in the sale of War Bonds. When the Four-Minute Men were absorbed by the Committee on Public Information, he went to Washington, DC to be its director. Woodrow Wilson sent him a letter of thanks. As the war came to a close he enlisted in the Army and trained in a New York base.