John Barry Mahool (September 14, 1870 – July 29, 1935) was the Mayor of Baltimore from 1907 to 1911.

[1] He became the Democratic nominee for Baltimore mayor in April 1907, defeating opponents John Charles Linthicum and George Stewart Brown.

610 prohibiting African-Americans from moving onto blocks where whites were the majority, and vice versa.

[3] Mahool had been an advocate for social justice, championing causes such as woman's suffrage, but the ordinance came in response to an uproar after George W. F. McMechen, an African-American Yale law school graduate, moved into a rich (white) neighborhood.

[5][6] Mahool died in Baltimore on July 29, 1935, nine days after suffering a fall in Ocean City, Maryland.