[2] Michael was the son of Cornelia "Amelia"[3] (née Morange; 1809–1881) and, supposedly, Miechel de Young (died 1854), who married in 1837.

[4] His maternal grandfather, Benjamin Morange, who served as the French Minister to Spain under Napoleon I,[5][6] moved to the United States about 1815[3] and helped found the B'nai Jeshurun Congregation in New York in 1825.

During a visit to New York City, De Young was inspired by the Metropolitan Museum of Art's location in Central Park.

Significantly, de Young owned about 31 blocks south of the park and could have been motivated by the fair's potential positive impacts on his real estate holdings.

De Young died on February 15, 1925; a Roman Catholic mass was held in St. Mary's Cathedral[15] (he had converted to Catholicism after marrying his wife, Katherine I.

[16] The M. H. de Young Memorial Museum in San Francisco's Golden Gate Park, is named in his honor.

[17] In 1956, one of De Young's grandsons, Ferdinand Melly Thieriot (1921–1956), the circulation director of The Chronicle, and his wife Frances (1921–1956), were among the 46 killed aboard the SS Andrea Doria when it was struck by the MS Stockholm off the coast of Nantucket.

[18] De Young was the grandfather of Nan Tucker McEvoy (1919–2015), chair of Chronicle Publishing Company's board of directors until the 1990s.